expr.py

from __future__ import annotations

import contextlib
import math
import operator
import os
import warnings
from datetime import timedelta
from functools import partial, reduce
from typing import (
    TYPE_CHECKING,
    Any,
    Callable,
    ClassVar,
    Collection,
    FrozenSet,
    Iterable,
    NoReturn,
    Sequence,
    Set,
    TypeVar,
)

import polars._reexport as pl
from polars import functions as F
from polars.datatypes import (
    Categorical,
    Null,
    Struct,
    UInt32,
    Utf8,
    is_polars_dtype,
    py_type_to_dtype,
)
from polars.dependencies import _check_for_numpy
from polars.dependencies import numpy as np
from polars.exceptions import PolarsInefficientMapWarning
from polars.expr.array import ExprArrayNameSpace
from polars.expr.binary import ExprBinaryNameSpace
from polars.expr.categorical import ExprCatNameSpace
from polars.expr.datetime import ExprDateTimeNameSpace
from polars.expr.list import ExprListNameSpace
from polars.expr.meta import ExprMetaNameSpace
from polars.expr.name import ExprNameNameSpace
from polars.expr.string import ExprStringNameSpace
from polars.expr.struct import ExprStructNameSpace
from polars.utils._parse_expr_input import (
    parse_as_expression,
    parse_as_list_of_expressions,
)
from polars.utils.convert import _negate_duration, _timedelta_to_pl_duration
from polars.utils.deprecation import (
    deprecate_function,
    deprecate_nonkeyword_arguments,
    deprecate_renamed_function,
    deprecate_renamed_parameter,
    deprecate_saturating,
    warn_closed_future_change,
)
from polars.utils.meta import threadpool_size
from polars.utils.various import no_default, sphinx_accessor

with contextlib.suppress(ImportError):  # Module not available when building docs
    from polars.polars import arg_where as py_arg_where
    from polars.polars import reduce as pyreduce

with contextlib.suppress(ImportError):  # Module not available when building docs
    from polars.polars import PyExpr

if TYPE_CHECKING:
    import sys

    from polars import DataFrame, LazyFrame, Series
    from polars.type_aliases import (
        ClosedInterval,
        FillNullStrategy,
        InterpolationMethod,
        IntoExpr,
        IntoExprColumn,
        MapElementsStrategy,
        NullBehavior,
        NumericLiteral,
        PolarsDataType,
        PythonLiteral,
        RankMethod,
        RollingInterpolationMethod,
        SearchSortedSide,
        TemporalLiteral,
        WindowMappingStrategy,
    )

    if sys.version_info >= (3, 11):
        from typing import Concatenate, ParamSpec, Self
    else:
        from typing_extensions import Concatenate, ParamSpec, Self

    T = TypeVar("T")
    P = ParamSpec("P")

elif os.getenv("BUILDING_SPHINX_DOCS"):
    property = sphinx_accessor


class Expr:
    """Expressions that can be used in various contexts."""

    _pyexpr: PyExpr = None
    _accessors: ClassVar[set[str]] = {
        "arr",
        "cat",
        "dt",
        "list",
        "meta",
        "name",
        "str",
        "bin",
        "struct",
    }

    @classmethod
    def _from_pyexpr(cls, pyexpr: PyExpr) -> Self:
        expr = cls.__new__(cls)
        expr._pyexpr = pyexpr
        return expr

    def _to_pyexpr(self, other: Any) -> PyExpr:
        if isinstance(other, Expr):
            return other._pyexpr
        else:
            return F.lit(other)._pyexpr

    def _repr_html_(self) -> str:
        return self._pyexpr.to_str()

    def __str__(self) -> str:
        return self._pyexpr.to_str()

    def __bool__(self) -> NoReturn:
        raise TypeError(
            "the truth value of an Expr is ambiguous"
            "\n\nHint: use '&' or '|' to logically combine Expr, not 'and'/'or', and"
            " use `x.is_in([y,z])` instead of `x in [y,z]` to check membership."
        )

    def __abs__(self) -> Self:
        return self.abs()

    # operators
    def __add__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr + self._to_pyexpr(other))

    def __radd__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) + self._pyexpr)

    def __and__(self, other: Expr | int | bool) -> Self:
        return self._from_pyexpr(self._pyexpr._and(self._to_pyexpr(other)))

    def __rand__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other)._and(self._pyexpr))

    def __eq__(self, other: Any) -> Self:  # type: ignore[override]
        return self._from_pyexpr(self._pyexpr.eq(self._to_pyexpr(other)))

    def __floordiv__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr // self._to_pyexpr(other))

    def __rfloordiv__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) // self._pyexpr)

    def __ge__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr.gt_eq(self._to_pyexpr(other)))

    def __gt__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr.gt(self._to_pyexpr(other)))

    def __invert__(self) -> Self:
        return self.not_()

    def __le__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr.lt_eq(self._to_pyexpr(other)))

    def __lt__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr.lt(self._to_pyexpr(other)))

    def __mod__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr % self._to_pyexpr(other))

    def __rmod__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) % self._pyexpr)

    def __mul__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr * self._to_pyexpr(other))

    def __rmul__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) * self._pyexpr)

    def __ne__(self, other: Any) -> Self:  # type: ignore[override]
        return self._from_pyexpr(self._pyexpr.neq(self._to_pyexpr(other)))

    def __neg__(self) -> Expr:
        neg_expr = F.lit(0) - self
        if (name := self.meta.output_name(raise_if_undetermined=False)) is not None:
            neg_expr = neg_expr.alias(name)
        return neg_expr

    def __or__(self, other: Expr | int | bool) -> Self:
        return self._from_pyexpr(self._pyexpr._or(self._to_pyexpr(other)))

    def __ror__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other)._or(self._pyexpr))

    def __pos__(self) -> Expr:
        pos_expr = F.lit(0) + self
        if (name := self.meta.output_name(raise_if_undetermined=False)) is not None:
            pos_expr = pos_expr.alias(name)
        return pos_expr

    def __pow__(self, power: int | float | Series | Expr) -> Self:
        return self.pow(power)

    def __rpow__(self, base: int | float | Expr) -> Expr:
        return self._from_pyexpr(parse_as_expression(base)) ** self

    def __sub__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr - self._to_pyexpr(other))

    def __rsub__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) - self._pyexpr)

    def __truediv__(self, other: Any) -> Self:
        return self._from_pyexpr(self._pyexpr / self._to_pyexpr(other))

    def __rtruediv__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other) / self._pyexpr)

    def __xor__(self, other: Expr | int | bool) -> Self:
        return self._from_pyexpr(self._pyexpr._xor(self._to_pyexpr(other)))

    def __rxor__(self, other: Any) -> Self:
        return self._from_pyexpr(self._to_pyexpr(other)._xor(self._pyexpr))

    def __getstate__(self) -> bytes:
        return self._pyexpr.__getstate__()

    def __setstate__(self, state: bytes) -> None:
        self._pyexpr = F.lit(0)._pyexpr  # Initialize with a dummy
        self._pyexpr.__setstate__(state)

    def __array_ufunc__(
        self, ufunc: Callable[..., Any], method: str, *inputs: Any, **kwargs: Any
    ) -> Self:
        """Numpy universal functions."""
        num_expr = sum(isinstance(inp, Expr) for inp in inputs)
        if num_expr > 1:
            if num_expr < len(inputs):
                raise ValueError(
                    "NumPy ufunc with more than one expression can only be used"
                    " if all non-expression inputs are provided as keyword arguments only"
                )

            exprs = parse_as_list_of_expressions(inputs)
            return self._from_pyexpr(pyreduce(partial(ufunc, **kwargs), exprs))

        def function(s: Series) -> Series:  # pragma: no cover
            args = [inp if not isinstance(inp, Expr) else s for inp in inputs]
            return ufunc(*args, **kwargs)

        return self.map_batches(function)

    @classmethod
    def from_json(cls, value: str) -> Self:
        """
        Read an expression from a JSON encoded string to construct an Expression.

        Parameters
        ----------
        value
            JSON encoded string value

        """
        expr = cls.__new__(cls)
        expr._pyexpr = PyExpr.meta_read_json(value)
        return expr

    def to_physical(self) -> Self:
        """
        Cast to physical representation of the logical dtype.

        - :func:`polars.datatypes.Date` -> :func:`polars.datatypes.Int32`
        - :func:`polars.datatypes.Datetime` -> :func:`polars.datatypes.Int64`
        - :func:`polars.datatypes.Time` -> :func:`polars.datatypes.Int64`
        - :func:`polars.datatypes.Duration` -> :func:`polars.datatypes.Int64`
        - :func:`polars.datatypes.Categorical` -> :func:`polars.datatypes.UInt32`
        - `List(inner)` -> `List(physical of inner)`

        Other data types will be left unchanged.

        Examples
        --------
        Replicating the pandas
        `pd.factorize
        <https://pandas.pydata.org/docs/reference/api/pandas.factorize.html>`_
        function.

        >>> pl.DataFrame({"vals": ["a", "x", None, "a"]}).with_columns(
        ...     [
        ...         pl.col("vals").cast(pl.Categorical),
        ...         pl.col("vals")
        ...         .cast(pl.Categorical)
        ...         .to_physical()
        ...         .alias("vals_physical"),
        ...     ]
        ... )
        shape: (4, 2)
        ┌──────┬───────────────┐
        │ vals ┆ vals_physical │
        │ ---  ┆ ---           │
        │ cat  ┆ u32           │
        ╞══════╪═══════════════╡
        │ a    ┆ 0             │
        │ x    ┆ 1             │
        │ null ┆ null          │
        │ a    ┆ 0             │
        └──────┴───────────────┘

        """
        return self._from_pyexpr(self._pyexpr.to_physical())

    @deprecate_renamed_parameter("drop_nulls", "ignore_nulls", version="0.19.0")
    def any(self, *, ignore_nulls: bool = True) -> Self:
        """
        Return whether any of the values in the column are `True`.

        Only works on columns of data type :class:`Boolean`.

        Parameters
        ----------
        ignore_nulls
            Ignore null values (default).

            If set to `False`, `Kleene logic`_ is used to deal with nulls:
            if the column contains any null values and no `True` values,
            the output is null.

            .. _Kleene logic: https://en.wikipedia.org/wiki/Three-valued_logic

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [True, False],
        ...         "b": [False, False],
        ...         "c": [None, False],
        ...     }
        ... )
        >>> df.select(pl.col("*").any())
        shape: (1, 3)
        ┌──────┬───────┬───────┐
        │ a    ┆ b     ┆ c     │
        │ ---  ┆ ---   ┆ ---   │
        │ bool ┆ bool  ┆ bool  │
        ╞══════╪═══════╪═══════╡
        │ true ┆ false ┆ false │
        └──────┴───────┴───────┘

        Enable Kleene logic by setting `ignore_nulls=False`.

        >>> df.select(pl.col("*").any(ignore_nulls=False))
        shape: (1, 3)
        ┌──────┬───────┬──────┐
        │ a    ┆ b     ┆ c    │
        │ ---  ┆ ---   ┆ ---  │
        │ bool ┆ bool  ┆ bool │
        ╞══════╪═══════╪══════╡
        │ true ┆ false ┆ null │
        └──────┴───────┴──────┘

        """
        return self._from_pyexpr(self._pyexpr.any(ignore_nulls))

    @deprecate_renamed_parameter("drop_nulls", "ignore_nulls", version="0.19.0")
    def all(self, *, ignore_nulls: bool = True) -> Self:
        """
        Return whether all values in the column are `True`.

        Only works on columns of data type :class:`Boolean`.

        .. note::
            This method is not to be confused with the function :func:`polars.all`,
            which can be used to select all columns.

        Parameters
        ----------
        ignore_nulls
            Ignore null values (default).

            If set to `False`, `Kleene logic`_ is used to deal with nulls:
            if the column contains any null values and no `True` values,
            the output is null.

            .. _Kleene logic: https://en.wikipedia.org/wiki/Three-valued_logic

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [True, True],
        ...         "b": [False, True],
        ...         "c": [None, True],
        ...     }
        ... )
        >>> df.select(pl.col("*").all())
        shape: (1, 3)
        ┌──────┬───────┬──────┐
        │ a    ┆ b     ┆ c    │
        │ ---  ┆ ---   ┆ ---  │
        │ bool ┆ bool  ┆ bool │
        ╞══════╪═══════╪══════╡
        │ true ┆ false ┆ true │
        └──────┴───────┴──────┘

        Enable Kleene logic by setting `ignore_nulls=False`.

        >>> df.select(pl.col("*").all(ignore_nulls=False))
        shape: (1, 3)
        ┌──────┬───────┬──────┐
        │ a    ┆ b     ┆ c    │
        │ ---  ┆ ---   ┆ ---  │
        │ bool ┆ bool  ┆ bool │
        ╞══════╪═══════╪══════╡
        │ true ┆ false ┆ null │
        └──────┴───────┴──────┘

        """
        return self._from_pyexpr(self._pyexpr.all(ignore_nulls))

    def arg_true(self) -> Self:
        """
        Return indices where expression evaluates `True`.

        .. warning::
            Modifies number of rows returned, so will fail in combination with other
            expressions. Use as only expression in `select` / `with_columns`.

        See Also
        --------
        Series.arg_true : Return indices where Series is True
        polars.arg_where

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2, 1]})
        >>> df.select((pl.col("a") == 1).arg_true())
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 0   │
        │ 1   │
        │ 3   │
        └─────┘

        """
        return self._from_pyexpr(py_arg_where(self._pyexpr))

    def sqrt(self) -> Self:
        """
        Compute the square root of the elements.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1.0, 2.0, 4.0]})
        >>> df.select(pl.col("values").sqrt())
        shape: (3, 1)
        ┌──────────┐
        │ values   │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.0      │
        │ 1.414214 │
        │ 2.0      │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.sqrt())

    def cbrt(self) -> Self:
        """
        Compute the cube root of the elements.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1.0, 2.0, 4.0]})
        >>> df.select(pl.col("values").cbrt())
        shape: (3, 1)
        ┌──────────┐
        │ values   │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.0      │
        │ 1.259921 │
        │ 1.587401 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.cbrt())

    def log10(self) -> Self:
        """
        Compute the base 10 logarithm of the input array, element-wise.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1.0, 2.0, 4.0]})
        >>> df.select(pl.col("values").log10())
        shape: (3, 1)
        ┌─────────┐
        │ values  │
        │ ---     │
        │ f64     │
        ╞═════════╡
        │ 0.0     │
        │ 0.30103 │
        │ 0.60206 │
        └─────────┘

        """
        return self.log(10.0)

    def exp(self) -> Self:
        """
        Compute the exponential, element-wise.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1.0, 2.0, 4.0]})
        >>> df.select(pl.col("values").exp())
        shape: (3, 1)
        ┌──────────┐
        │ values   │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 2.718282 │
        │ 7.389056 │
        │ 54.59815 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.exp())

    def alias(self, name: str) -> Self:
        """
        Rename the expression.

        Parameters
        ----------
        name
            The new name.

        See Also
        --------
        map
        prefix
        suffix

        Examples
        --------
        Rename an expression to avoid overwriting an existing column.

        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": ["x", "y", "z"],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("a") + 10,
        ...     pl.col("b").str.to_uppercase().alias("c"),
        ... )
        shape: (3, 3)
        ┌─────┬─────┬─────┐
        │ a   ┆ b   ┆ c   │
        │ --- ┆ --- ┆ --- │
        │ i64 ┆ str ┆ str │
        ╞═════╪═════╪═════╡
        │ 11  ┆ x   ┆ X   │
        │ 12  ┆ y   ┆ Y   │
        │ 13  ┆ z   ┆ Z   │
        └─────┴─────┴─────┘

        Overwrite the default name of literal columns to prevent errors due to duplicate
        column names.

        >>> df.with_columns(
        ...     pl.lit(True).alias("c"),
        ...     pl.lit(4.0).alias("d"),
        ... )
        shape: (3, 4)
        ┌─────┬─────┬──────┬─────┐
        │ a   ┆ b   ┆ c    ┆ d   │
        │ --- ┆ --- ┆ ---  ┆ --- │
        │ i64 ┆ str ┆ bool ┆ f64 │
        ╞═════╪═════╪══════╪═════╡
        │ 1   ┆ x   ┆ true ┆ 4.0 │
        │ 2   ┆ y   ┆ true ┆ 4.0 │
        │ 3   ┆ z   ┆ true ┆ 4.0 │
        └─────┴─────┴──────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.alias(name))

    @deprecate_renamed_function("name.map", moved=True, version="0.19.12")
    def map_alias(self, function: Callable[[str], str]) -> Self:
        """
        Rename the output of an expression by mapping a function over the root name.

        .. deprecated:: 0.19.12
            This method has been renamed to :func:`name.map`.

        Parameters
        ----------
        function
            Function that maps a root name to a new name.

        See Also
        --------
        keep_name
        prefix
        suffix

        Examples
        --------
        Remove a common suffix and convert to lower case.

        >>> df = pl.DataFrame(
        ...     {
        ...         "A_reverse": [3, 2, 1],
        ...         "B_reverse": ["z", "y", "x"],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.all().reverse().name.map(lambda c: c.rstrip("_reverse").lower())
        ... )
        shape: (3, 4)
        ┌───────────┬───────────┬─────┬─────┐
        │ A_reverse ┆ B_reverse ┆ a   ┆ b   │
        │ ---       ┆ ---       ┆ --- ┆ --- │
        │ i64       ┆ str       ┆ i64 ┆ str │
        ╞═══════════╪═══════════╪═════╪═════╡
        │ 3         ┆ z         ┆ 1   ┆ x   │
        │ 2         ┆ y         ┆ 2   ┆ y   │
        │ 1         ┆ x         ┆ 3   ┆ z   │
        └───────────┴───────────┴─────┴─────┘

        """
        return self.name.map(function)  # type: ignore[return-value]

    @deprecate_renamed_function("name.prefix", moved=True, version="0.19.12")
    def prefix(self, prefix: str) -> Self:
        """
        Add a prefix to the root column name of the expression.

        .. deprecated:: 0.19.12
            This method has been renamed to :func:`name.prefix`.

        Parameters
        ----------
        prefix
            Prefix to add to the root column name.

        Notes
        -----
        This will undo any previous renaming operations on the expression.

        Due to implementation constraints, this method can only be called as the last
        expression in a chain.

        See Also
        --------
        suffix

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": ["x", "y", "z"],
        ...     }
        ... )
        >>> df.with_columns(pl.all().reverse().name.prefix("reverse_"))
        shape: (3, 4)
        ┌─────┬─────┬───────────┬───────────┐
        │ a   ┆ b   ┆ reverse_a ┆ reverse_b │
        │ --- ┆ --- ┆ ---       ┆ ---       │
        │ i64 ┆ str ┆ i64       ┆ str       │
        ╞═════╪═════╪═══════════╪═══════════╡
        │ 1   ┆ x   ┆ 3         ┆ z         │
        │ 2   ┆ y   ┆ 2         ┆ y         │
        │ 3   ┆ z   ┆ 1         ┆ x         │
        └─────┴─────┴───────────┴───────────┘

        """
        return self.name.prefix(prefix)  # type: ignore[return-value]

    @deprecate_renamed_function("name.suffix", moved=True, version="0.19.12")
    def suffix(self, suffix: str) -> Self:
        """
        Add a suffix to the root column name of the expression.

        .. deprecated:: 0.19.12
            This method has been renamed to :func:`name.suffix`.

        Parameters
        ----------
        suffix
            Suffix to add to the root column name.

        Notes
        -----
        This will undo any previous renaming operations on the expression.

        Due to implementation constraints, this method can only be called as the last
        expression in a chain.

        See Also
        --------
        prefix

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": ["x", "y", "z"],
        ...     }
        ... )
        >>> df.with_columns(pl.all().reverse().name.suffix("_reverse"))
        shape: (3, 4)
        ┌─────┬─────┬───────────┬───────────┐
        │ a   ┆ b   ┆ a_reverse ┆ b_reverse │
        │ --- ┆ --- ┆ ---       ┆ ---       │
        │ i64 ┆ str ┆ i64       ┆ str       │
        ╞═════╪═════╪═══════════╪═══════════╡
        │ 1   ┆ x   ┆ 3         ┆ z         │
        │ 2   ┆ y   ┆ 2         ┆ y         │
        │ 3   ┆ z   ┆ 1         ┆ x         │
        └─────┴─────┴───────────┴───────────┘

        """
        return self.name.suffix(suffix)  # type: ignore[return-value]

    @deprecate_renamed_function("name.keep", moved=True, version="0.19.12")
    def keep_name(self) -> Self:
        """
        Keep the original root name of the expression.

        .. deprecated:: 0.19.12
            This method has been renamed to :func:`name.keep`.

        Notes
        -----
        Due to implementation constraints, this method can only be called as the last
        expression in a chain.

        See Also
        --------
        alias

        Examples
        --------
        Undo an alias operation.

        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2],
        ...         "b": [3, 4],
        ...     }
        ... )
        >>> df.with_columns((pl.col("a") * 9).alias("c").name.keep())
        shape: (2, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 9   ┆ 3   │
        │ 18  ┆ 4   │
        └─────┴─────┘

        Prevent errors due to duplicate column names.

        >>> df.select((pl.lit(10) / pl.all()).name.keep())
        shape: (2, 2)
        ┌──────┬──────────┐
        │ a    ┆ b        │
        │ ---  ┆ ---      │
        │ f64  ┆ f64      │
        ╞══════╪══════════╡
        │ 10.0 ┆ 3.333333 │
        │ 5.0  ┆ 2.5      │
        └──────┴──────────┘

        """
        return self.name.keep()  # type: ignore[return-value]

    def exclude(
        self,
        columns: str | PolarsDataType | Collection[str] | Collection[PolarsDataType],
        *more_columns: str | PolarsDataType,
    ) -> Self:
        """
        Exclude columns from a multi-column expression.

        Only works after a wildcard or regex column selection, and you cannot provide
        both string column names *and* dtypes (you may prefer to use selectors instead).

        Parameters
        ----------
        columns
            The name or datatype of the column(s) to exclude. Accepts regular expression
            input. Regular expressions should start with `^` and end with `$`.
        *more_columns
            Additional names or datatypes of columns to exclude, specified as positional
            arguments.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "aa": [1, 2, 3],
        ...         "ba": ["a", "b", None],
        ...         "cc": [None, 2.5, 1.5],
        ...     }
        ... )
        >>> df
        shape: (3, 3)
        ┌─────┬──────┬──────┐
        │ aa  ┆ ba   ┆ cc   │
        │ --- ┆ ---  ┆ ---  │
        │ i64 ┆ str  ┆ f64  │
        ╞═════╪══════╪══════╡
        │ 1   ┆ a    ┆ null │
        │ 2   ┆ b    ┆ 2.5  │
        │ 3   ┆ null ┆ 1.5  │
        └─────┴──────┴──────┘

        Exclude by column name(s):

        >>> df.select(pl.all().exclude("ba"))
        shape: (3, 2)
        ┌─────┬──────┐
        │ aa  ┆ cc   │
        │ --- ┆ ---  │
        │ i64 ┆ f64  │
        ╞═════╪══════╡
        │ 1   ┆ null │
        │ 2   ┆ 2.5  │
        │ 3   ┆ 1.5  │
        └─────┴──────┘

        Exclude by regex, e.g. removing all columns whose names end with the letter "a":

        >>> df.select(pl.all().exclude("^.*a$"))
        shape: (3, 1)
        ┌──────┐
        │ cc   │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ null │
        │ 2.5  │
        │ 1.5  │
        └──────┘

        Exclude by dtype(s), e.g. removing all columns of type Int64 or Float64:

        >>> df.select(pl.all().exclude([pl.Int64, pl.Float64]))
        shape: (3, 1)
        ┌──────┐
        │ ba   │
        │ ---  │
        │ str  │
        ╞══════╡
        │ a    │
        │ b    │
        │ null │
        └──────┘

        """
        exclude_cols: list[str] = []
        exclude_dtypes: list[PolarsDataType] = []
        for item in (
            *(
                columns
                if isinstance(columns, Collection) and not isinstance(columns, str)
                else [columns]
            ),
            *more_columns,
        ):
            if isinstance(item, str):
                exclude_cols.append(item)
            elif is_polars_dtype(item):
                exclude_dtypes.append(item)
            else:
                raise TypeError(
                    "invalid input for `exclude`"
                    f"\n\nExpected one or more `str`, `DataType`, or selector; found {type(item).__name__!r} instead."
                )

        if exclude_cols and exclude_dtypes:
            raise TypeError(
                "cannot exclude by both column name and dtype; use a selector instead"
            )
        elif exclude_dtypes:
            return self._from_pyexpr(self._pyexpr.exclude_dtype(exclude_dtypes))
        else:
            return self._from_pyexpr(self._pyexpr.exclude(exclude_cols))

    def pipe(
        self,
        function: Callable[Concatenate[Expr, P], T],
        *args: P.args,
        **kwargs: P.kwargs,
    ) -> T:
        r'''
        Offers a structured way to apply a sequence of user-defined functions (UDFs).

        Parameters
        ----------
        function
            Callable; will receive the expression as the first parameter,
            followed by any given args/kwargs.
        *args
            Arguments to pass to the UDF.
        **kwargs
            Keyword arguments to pass to the UDF.

        Examples
        --------
        >>> def extract_number(expr: pl.Expr) -> pl.Expr:
        ...     """Extract the digits from a string."""
        ...     return expr.str.extract(r"\d+", 0).cast(pl.Int64)
        >>>
        >>> def scale_negative_even(expr: pl.Expr, *, n: int = 1) -> pl.Expr:
        ...     """Set even numbers negative, and scale by a user-supplied value."""
        ...     expr = pl.when(expr % 2 == 0).then(-expr).otherwise(expr)
        ...     return expr * n
        >>>
        >>> df = pl.DataFrame({"val": ["a: 1", "b: 2", "c: 3", "d: 4"]})
        >>> df.with_columns(
        ...     udfs=(
        ...         pl.col("val").pipe(extract_number).pipe(scale_negative_even, n=5)
        ...     ),
        ... )
        shape: (4, 2)
        ┌──────┬──────┐
        │ val  ┆ udfs │
        │ ---  ┆ ---  │
        │ str  ┆ i64  │
        ╞══════╪══════╡
        │ a: 1 ┆ 5    │
        │ b: 2 ┆ -10  │
        │ c: 3 ┆ 15   │
        │ d: 4 ┆ -20  │
        └──────┴──────┘

        '''
        return function(self, *args, **kwargs)

    @deprecate_renamed_function("not_", version="0.19.2")
    def is_not(self) -> Self:
        """
        Negate a boolean expression.

        .. deprecated:: 0.19.2
            This method has been renamed to :func:`Expr.not_`.

        """
        return self.not_()

    def not_(self) -> Self:
        """
        Negate a boolean expression.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [True, False, False],
        ...         "b": ["a", "b", None],
        ...     }
        ... )
        >>> df
        shape: (3, 2)
        ┌───────┬──────┐
        │ a     ┆ b    │
        │ ---   ┆ ---  │
        │ bool  ┆ str  │
        ╞═══════╪══════╡
        │ true  ┆ a    │
        │ false ┆ b    │
        │ false ┆ null │
        └───────┴──────┘
        >>> df.select(pl.col("a").not_())
        shape: (3, 1)
        ┌───────┐
        │ a     │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ false │
        │ true  │
        │ true  │
        └───────┘

        """
        return self._from_pyexpr(self._pyexpr.not_())

    def is_null(self) -> Self:
        """
        Returns a boolean Series indicating which values are null.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None, 1, 5],
        ...         "b": [1.0, 2.0, float("nan"), 1.0, 5.0],
        ...     }
        ... )
        >>> df.with_columns(pl.all().is_null().name.suffix("_isnull"))  # nan != null
        shape: (5, 4)
        ┌──────┬─────┬──────────┬──────────┐
        │ a    ┆ b   ┆ a_isnull ┆ b_isnull │
        │ ---  ┆ --- ┆ ---      ┆ ---      │
        │ i64  ┆ f64 ┆ bool     ┆ bool     │
        ╞══════╪═════╪══════════╪══════════╡
        │ 1    ┆ 1.0 ┆ false    ┆ false    │
        │ 2    ┆ 2.0 ┆ false    ┆ false    │
        │ null ┆ NaN ┆ true     ┆ false    │
        │ 1    ┆ 1.0 ┆ false    ┆ false    │
        │ 5    ┆ 5.0 ┆ false    ┆ false    │
        └──────┴─────┴──────────┴──────────┘

        """
        return self._from_pyexpr(self._pyexpr.is_null())

    def is_not_null(self) -> Self:
        """
        Returns a boolean Series indicating which values are not null.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None, 1, 5],
        ...         "b": [1.0, 2.0, float("nan"), 1.0, 5.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.all().is_not_null().name.suffix("_not_null")  # nan != null
        ... )
        shape: (5, 4)
        ┌──────┬─────┬────────────┬────────────┐
        │ a    ┆ b   ┆ a_not_null ┆ b_not_null │
        │ ---  ┆ --- ┆ ---        ┆ ---        │
        │ i64  ┆ f64 ┆ bool       ┆ bool       │
        ╞══════╪═════╪════════════╪════════════╡
        │ 1    ┆ 1.0 ┆ true       ┆ true       │
        │ 2    ┆ 2.0 ┆ true       ┆ true       │
        │ null ┆ NaN ┆ false      ┆ true       │
        │ 1    ┆ 1.0 ┆ true       ┆ true       │
        │ 5    ┆ 5.0 ┆ true       ┆ true       │
        └──────┴─────┴────────────┴────────────┘

        """
        return self._from_pyexpr(self._pyexpr.is_not_null())

    def is_finite(self) -> Self:
        """
        Returns a boolean Series indicating which values are finite.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "A": [1.0, 2],
        ...         "B": [3.0, float("inf")],
        ...     }
        ... )
        >>> df.select(pl.all().is_finite())
        shape: (2, 2)
        ┌──────┬───────┐
        │ A    ┆ B     │
        │ ---  ┆ ---   │
        │ bool ┆ bool  │
        ╞══════╪═══════╡
        │ true ┆ true  │
        │ true ┆ false │
        └──────┴───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_finite())

    def is_infinite(self) -> Self:
        """
        Returns a boolean Series indicating which values are infinite.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "A": [1.0, 2],
        ...         "B": [3.0, float("inf")],
        ...     }
        ... )
        >>> df.select(pl.all().is_infinite())
        shape: (2, 2)
        ┌───────┬───────┐
        │ A     ┆ B     │
        │ ---   ┆ ---   │
        │ bool  ┆ bool  │
        ╞═══════╪═══════╡
        │ false ┆ false │
        │ false ┆ true  │
        └───────┴───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_infinite())

    def is_nan(self) -> Self:
        """
        Returns a boolean Series indicating which values are NaN.

        Notes
        -----
        Floating point `NaN` (Not A Number) should not be confused
        with missing data represented as `Null/None`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None, 1, 5],
        ...         "b": [1.0, 2.0, float("nan"), 1.0, 5.0],
        ...     }
        ... )
        >>> df.with_columns(pl.col(pl.Float64).is_nan().name.suffix("_isnan"))
        shape: (5, 3)
        ┌──────┬─────┬─────────┐
        │ a    ┆ b   ┆ b_isnan │
        │ ---  ┆ --- ┆ ---     │
        │ i64  ┆ f64 ┆ bool    │
        ╞══════╪═════╪═════════╡
        │ 1    ┆ 1.0 ┆ false   │
        │ 2    ┆ 2.0 ┆ false   │
        │ null ┆ NaN ┆ true    │
        │ 1    ┆ 1.0 ┆ false   │
        │ 5    ┆ 5.0 ┆ false   │
        └──────┴─────┴─────────┘

        """
        return self._from_pyexpr(self._pyexpr.is_nan())

    def is_not_nan(self) -> Self:
        """
        Returns a boolean Series indicating which values are not NaN.

        Notes
        -----
        Floating point `NaN` (Not A Number) should not be confused
        with missing data represented as `Null/None`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None, 1, 5],
        ...         "b": [1.0, 2.0, float("nan"), 1.0, 5.0],
        ...     }
        ... )
        >>> df.with_columns(pl.col(pl.Float64).is_not_nan().name.suffix("_is_not_nan"))
        shape: (5, 3)
        ┌──────┬─────┬──────────────┐
        │ a    ┆ b   ┆ b_is_not_nan │
        │ ---  ┆ --- ┆ ---          │
        │ i64  ┆ f64 ┆ bool         │
        ╞══════╪═════╪══════════════╡
        │ 1    ┆ 1.0 ┆ true         │
        │ 2    ┆ 2.0 ┆ true         │
        │ null ┆ NaN ┆ false        │
        │ 1    ┆ 1.0 ┆ true         │
        │ 5    ┆ 5.0 ┆ true         │
        └──────┴─────┴──────────────┘

        """
        return self._from_pyexpr(self._pyexpr.is_not_nan())

    def agg_groups(self) -> Self:
        """
        Get the group indexes of the group by operation.

        Should be used in aggregation context only.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group": [
        ...             "one",
        ...             "one",
        ...             "one",
        ...             "two",
        ...             "two",
        ...             "two",
        ...         ],
        ...         "value": [94, 95, 96, 97, 97, 99],
        ...     }
        ... )
        >>> df.group_by("group", maintain_order=True).agg(pl.col("value").agg_groups())
        shape: (2, 2)
        ┌───────┬───────────┐
        │ group ┆ value     │
        │ ---   ┆ ---       │
        │ str   ┆ list[u32] │
        ╞═══════╪═══════════╡
        │ one   ┆ [0, 1, 2] │
        │ two   ┆ [3, 4, 5] │
        └───────┴───────────┘

        """
        return self._from_pyexpr(self._pyexpr.agg_groups())

    def count(self) -> Self:
        """
        Return the number of elements in the column.

        .. warning::
            Null values are treated like regular elements in this context.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [8, 9, 10], "b": [None, 4, 4]})
        >>> df.select(pl.all().count())
        shape: (1, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ u32 ┆ u32 │
        ╞═════╪═════╡
        │ 3   ┆ 3   │
        └─────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.count())

    def len(self) -> Self:
        """
        Return the number of elements in the column.

        Null values are treated like regular elements in this context.

        Alias for :func:`count`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [8, 9, 10], "b": [None, 4, 4]})
        >>> df.select(pl.all().len())
        shape: (1, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ u32 ┆ u32 │
        ╞═════╪═════╡
        │ 3   ┆ 3   │
        └─────┴─────┘

        """
        return self.count()

    def slice(self, offset: int | Expr, length: int | Expr | None = None) -> Self:
        """
        Get a slice of this expression.

        Parameters
        ----------
        offset
            Start index. Negative indexing is supported.
        length
            Length of the slice. If set to `None`, all rows starting at the offset
            will be selected.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [8, 9, 10, 11],
        ...         "b": [None, 4, 4, 4],
        ...     }
        ... )
        >>> df.select(pl.all().slice(1, 2))
        shape: (2, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 9   ┆ 4   │
        │ 10  ┆ 4   │
        └─────┴─────┘

        """
        if not isinstance(offset, Expr):
            offset = F.lit(offset)
        if not isinstance(length, Expr):
            length = F.lit(length)
        return self._from_pyexpr(self._pyexpr.slice(offset._pyexpr, length._pyexpr))

    def append(self, other: IntoExpr, *, upcast: bool = True) -> Self:
        """
        Append expressions.

        This is done by adding the chunks of `other` to this `Series`.

        Parameters
        ----------
        other
            Expression to append.
        upcast
            Cast both `Series` to the same supertype.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [8, 9, 10],
        ...         "b": [None, 4, 4],
        ...     }
        ... )
        >>> df.select(pl.all().head(1).append(pl.all().tail(1)))
        shape: (2, 2)
        ┌─────┬──────┐
        │ a   ┆ b    │
        │ --- ┆ ---  │
        │ i64 ┆ i64  │
        ╞═════╪══════╡
        │ 8   ┆ null │
        │ 10  ┆ 4    │
        └─────┴──────┘

        """
        other = parse_as_expression(other)
        return self._from_pyexpr(self._pyexpr.append(other, upcast))

    def rechunk(self) -> Self:
        """
        Create a single chunk of memory for this Series.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})

        Create a Series with 3 nulls, append column a then rechunk

        >>> df.select(pl.repeat(None, 3).append(pl.col("a")).rechunk())
        shape: (6, 1)
        ┌────────┐
        │ repeat │
        │ ---    │
        │ i64    │
        ╞════════╡
        │ null   │
        │ null   │
        │ null   │
        │ 1      │
        │ 1      │
        │ 2      │
        └────────┘

        """
        return self._from_pyexpr(self._pyexpr.rechunk())

    def drop_nulls(self) -> Self:
        """
        Drop all null values.

        The original order of the remaining elements is preserved.

        See Also
        --------
        drop_nans

        Notes
        -----
        A null value is not the same as a NaN value.
        To drop NaN values, use :func:`drop_nans`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0, None, 3.0, float("nan")]})
        >>> df.select(pl.col("a").drop_nulls())
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        │ 3.0 │
        │ NaN │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.drop_nulls())

    def drop_nans(self) -> Self:
        """
        Drop all floating point NaN values.

        The original order of the remaining elements is preserved.

        See Also
        --------
        drop_nulls

        Notes
        -----
        A NaN value is not the same as a null value.
        To drop null values, use :func:`drop_nulls`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0, None, 3.0, float("nan")]})
        >>> df.select(pl.col("a").drop_nans())
        shape: (3, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ 1.0  │
        │ null │
        │ 3.0  │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.drop_nans())

    def cum_sum(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative sum computed at every element.

        Parameters
        ----------
        reverse
            Reverse the operation.

        Notes
        -----
        Dtypes in {Int8, UInt8, Int16, UInt16} are cast to
        Int64 before summing to prevent overflow issues.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("a").cum_sum().alias("cum_sum"),
        ...     pl.col("a").cum_sum(reverse=True).alias("cum_sum_reverse"),
        ... )
        shape: (4, 3)
        ┌─────┬─────────┬─────────────────┐
        │ a   ┆ cum_sum ┆ cum_sum_reverse │
        │ --- ┆ ---     ┆ ---             │
        │ i64 ┆ i64     ┆ i64             │
        ╞═════╪═════════╪═════════════════╡
        │ 1   ┆ 1       ┆ 10              │
        │ 2   ┆ 3       ┆ 9               │
        │ 3   ┆ 6       ┆ 7               │
        │ 4   ┆ 10      ┆ 4               │
        └─────┴─────────┴─────────────────┘

        Null values are excluded, but can also be filled by calling `forward_fill`.

        >>> df = pl.DataFrame({"values": [None, 10, None, 8, 9, None, 16, None]})
        >>> df.with_columns(
        ...     pl.col("values").cum_sum().alias("value_cum_sum"),
        ...     pl.col("values")
        ...     .cum_sum()
        ...     .forward_fill()
        ...     .alias("value_cum_sum_all_filled"),
        ... )
        shape: (8, 3)
        ┌────────┬───────────────┬──────────────────────────┐
        │ values ┆ value_cum_sum ┆ value_cum_sum_all_filled │
        │ ---    ┆ ---           ┆ ---                      │
        │ i64    ┆ i64           ┆ i64                      │
        ╞════════╪═══════════════╪══════════════════════════╡
        │ null   ┆ null          ┆ null                     │
        │ 10     ┆ 10            ┆ 10                       │
        │ null   ┆ null          ┆ 10                       │
        │ 8      ┆ 18            ┆ 18                       │
        │ 9      ┆ 27            ┆ 27                       │
        │ null   ┆ null          ┆ 27                       │
        │ 16     ┆ 43            ┆ 43                       │
        │ null   ┆ null          ┆ 43                       │
        └────────┴───────────────┴──────────────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.cum_sum(reverse))

    def cum_prod(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative product computed at every element.

        Parameters
        ----------
        reverse
            Reverse the operation.

        Notes
        -----
        Dtypes in {Int8, UInt8, Int16, UInt16} are cast to
        Int64 before summing to prevent overflow issues.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("a").cum_prod().alias("cum_prod"),
        ...     pl.col("a").cum_prod(reverse=True).alias("cum_prod_reverse"),
        ... )
        shape: (4, 3)
        ┌─────┬──────────┬──────────────────┐
        │ a   ┆ cum_prod ┆ cum_prod_reverse │
        │ --- ┆ ---      ┆ ---              │
        │ i64 ┆ i64      ┆ i64              │
        ╞═════╪══════════╪══════════════════╡
        │ 1   ┆ 1        ┆ 24               │
        │ 2   ┆ 2        ┆ 24               │
        │ 3   ┆ 6        ┆ 12               │
        │ 4   ┆ 24       ┆ 4                │
        └─────┴──────────┴──────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.cum_prod(reverse))

    def cum_min(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative min computed at every element.

        Parameters
        ----------
        reverse
            Reverse the operation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("a").cum_min().alias("cum_min"),
        ...     pl.col("a").cum_min(reverse=True).alias("cum_min_reverse"),
        ... )
        shape: (4, 3)
        ┌─────┬─────────┬─────────────────┐
        │ a   ┆ cum_min ┆ cum_min_reverse │
        │ --- ┆ ---     ┆ ---             │
        │ i64 ┆ i64     ┆ i64             │
        ╞═════╪═════════╪═════════════════╡
        │ 1   ┆ 1       ┆ 1               │
        │ 2   ┆ 1       ┆ 2               │
        │ 3   ┆ 1       ┆ 3               │
        │ 4   ┆ 1       ┆ 4               │
        └─────┴─────────┴─────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.cum_min(reverse))

    def cum_max(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative max computed at every element.

        Parameters
        ----------
        reverse
            Reverse the operation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("a").cum_max().alias("cum_max"),
        ...     pl.col("a").cum_max(reverse=True).alias("cum_max_reverse"),
        ... )
        shape: (4, 3)
        ┌─────┬─────────┬─────────────────┐
        │ a   ┆ cum_max ┆ cum_max_reverse │
        │ --- ┆ ---     ┆ ---             │
        │ i64 ┆ i64     ┆ i64             │
        ╞═════╪═════════╪═════════════════╡
        │ 1   ┆ 1       ┆ 4               │
        │ 2   ┆ 2       ┆ 4               │
        │ 3   ┆ 3       ┆ 4               │
        │ 4   ┆ 4       ┆ 4               │
        └─────┴─────────┴─────────────────┘

        Null values are excluded, but can also be filled by calling `forward_fill`.

        >>> df = pl.DataFrame({"values": [None, 10, None, 8, 9, None, 16, None]})
        >>> df.with_columns(
        ...     pl.col("values").cum_max().alias("cum_max"),
        ...     pl.col("values").cum_max().forward_fill().alias("cum_max_all_filled"),
        ... )
        shape: (8, 3)
        ┌────────┬─────────┬────────────────────┐
        │ values ┆ cum_max ┆ cum_max_all_filled │
        │ ---    ┆ ---     ┆ ---                │
        │ i64    ┆ i64     ┆ i64                │
        ╞════════╪═════════╪════════════════════╡
        │ null   ┆ null    ┆ null               │
        │ 10     ┆ 10      ┆ 10                 │
        │ null   ┆ null    ┆ 10                 │
        │ 8      ┆ 10      ┆ 10                 │
        │ 9      ┆ 10      ┆ 10                 │
        │ null   ┆ null    ┆ 10                 │
        │ 16     ┆ 16      ┆ 16                 │
        │ null   ┆ null    ┆ 16                 │
        └────────┴─────────┴────────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.cum_max(reverse))

    def cum_count(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative count computed at every element.

        Counting from 0 to len

        Parameters
        ----------
        reverse
            Reverse the operation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("a").cum_count().alias("cum_count"),
        ...     pl.col("a").cum_count(reverse=True).alias("cum_count_reverse"),
        ... )
        shape: (4, 3)
        ┌─────┬───────────┬───────────────────┐
        │ a   ┆ cum_count ┆ cum_count_reverse │
        │ --- ┆ ---       ┆ ---               │
        │ i64 ┆ u32       ┆ u32               │
        ╞═════╪═══════════╪═══════════════════╡
        │ 1   ┆ 0         ┆ 3                 │
        │ 2   ┆ 1         ┆ 2                 │
        │ 3   ┆ 2         ┆ 1                 │
        │ 4   ┆ 3         ┆ 0                 │
        └─────┴───────────┴───────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.cum_count(reverse))

    def floor(self) -> Self:
        """
        Rounds down to the nearest integer value.

        Only works on floating point Series.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.3, 0.5, 1.0, 1.1]})
        >>> df.select(pl.col("a").floor())
        shape: (4, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.0 │
        │ 0.0 │
        │ 1.0 │
        │ 1.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.floor())

    def ceil(self) -> Self:
        """
        Rounds up to the nearest integer value.

        Only works on floating point Series.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.3, 0.5, 1.0, 1.1]})
        >>> df.select(pl.col("a").ceil())
        shape: (4, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        │ 1.0 │
        │ 1.0 │
        │ 2.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.ceil())

    def round(self, decimals: int = 0) -> Self:
        """
        Round underlying floating point data by `decimals` digits.

        Parameters
        ----------
        decimals
            Number of decimals to round by.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.33, 0.52, 1.02, 1.17]})
        >>> df.select(pl.col("a").round(1))
        shape: (4, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.3 │
        │ 0.5 │
        │ 1.0 │
        │ 1.2 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.round(decimals))

    def round_sig_figs(self, digits: int) -> Self:
        """
        Round to a number of significant figures.

        Parameters
        ----------
        digits
            Number of significant figures to round to.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.01234, 3.333, 1234.0]})
        >>> df.with_columns(pl.col("a").round_sig_figs(2).alias("round_sig_figs"))
        shape: (3, 2)
        ┌─────────┬────────────────┐
        │ a       ┆ round_sig_figs │
        │ ---     ┆ ---            │
        │ f64     ┆ f64            │
        ╞═════════╪════════════════╡
        │ 0.01234 ┆ 0.012          │
        │ 3.333   ┆ 3.3            │
        │ 1234.0  ┆ 1200.0         │
        └─────────┴────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.round_sig_figs(digits))

    def dot(self, other: Expr | str) -> Self:
        """
        Compute the dot/inner product between two Expressions.

        Parameters
        ----------
        other
            Expression to compute dot product with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 3, 5],
        ...         "b": [2, 4, 6],
        ...     }
        ... )
        >>> df.select(pl.col("a").dot(pl.col("b")))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 44  │
        └─────┘

        """
        other = parse_as_expression(other)
        return self._from_pyexpr(self._pyexpr.dot(other))

    def mode(self) -> Self:
        """
        Compute the most occurring value(s).

        Can return multiple Values.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 1, 2, 3],
        ...         "b": [1, 1, 2, 2],
        ...     }
        ... )
        >>> df.select(pl.all().mode())  # doctest: +IGNORE_RESULT
        shape: (2, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 1   ┆ 1   │
        │ 1   ┆ 2   │
        └─────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.mode())

    def cast(self, dtype: PolarsDataType | type[Any], *, strict: bool = True) -> Self:
        """
        Cast between data types.

        Parameters
        ----------
        dtype
            DataType to cast to.
        strict
            Throw an error if a cast could not be done (for instance, due to an
            overflow).

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": ["4", "5", "6"],
        ...     }
        ... )
        >>> df.with_columns(
        ...     [
        ...         pl.col("a").cast(pl.Float64),
        ...         pl.col("b").cast(pl.Int32),
        ...     ]
        ... )
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ f64 ┆ i32 │
        ╞═════╪═════╡
        │ 1.0 ┆ 4   │
        │ 2.0 ┆ 5   │
        │ 3.0 ┆ 6   │
        └─────┴─────┘

        """
        dtype = py_type_to_dtype(dtype)
        return self._from_pyexpr(self._pyexpr.cast(dtype, strict))

    def sort(self, *, descending: bool = False, nulls_last: bool = False) -> Self:
        """
        Sort this column.

        When used in a projection/selection context, the whole column is sorted.
        When used in a group by context, the groups are sorted.

        Parameters
        ----------
        descending
            Sort in descending order.
        nulls_last
            Place null values last.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, None, 3, 2],
        ...     }
        ... )
        >>> df.select(pl.col("a").sort())
        shape: (4, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ i64  │
        ╞══════╡
        │ null │
        │ 1    │
        │ 2    │
        │ 3    │
        └──────┘
        >>> df.select(pl.col("a").sort(descending=True))
        shape: (4, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ i64  │
        ╞══════╡
        │ null │
        │ 3    │
        │ 2    │
        │ 1    │
        └──────┘
        >>> df.select(pl.col("a").sort(nulls_last=True))
        shape: (4, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ i64  │
        ╞══════╡
        │ 1    │
        │ 2    │
        │ 3    │
        │ null │
        └──────┘

        When sorting in a group by context, the groups are sorted.

        >>> df = pl.DataFrame(
        ...     {
        ...         "group": ["one", "one", "one", "two", "two", "two"],
        ...         "value": [1, 98, 2, 3, 99, 4],
        ...     }
        ... )
        >>> df.group_by("group").agg(pl.col("value").sort())  # doctest: +IGNORE_RESULT
        shape: (2, 2)
        ┌───────┬────────────┐
        │ group ┆ value      │
        │ ---   ┆ ---        │
        │ str   ┆ list[i64]  │
        ╞═══════╪════════════╡
        │ two   ┆ [3, 4, 99] │
        │ one   ┆ [1, 2, 98] │
        └───────┴────────────┘

        """
        return self._from_pyexpr(self._pyexpr.sort_with(descending, nulls_last))

    def top_k(self, k: int | IntoExprColumn = 5) -> Self:
        r"""
        Return the `k` largest elements.

        This has time complexity:

        .. math:: O(n + k \\log{}n - \frac{k}{2})

        Parameters
        ----------
        k
            Number of elements to return.

        See Also
        --------
        bottom_k

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "value": [1, 98, 2, 3, 99, 4],
        ...     }
        ... )
        >>> df.select(
        ...     [
        ...         pl.col("value").top_k().alias("top_k"),
        ...         pl.col("value").bottom_k().alias("bottom_k"),
        ...     ]
        ... )
        shape: (5, 2)
        ┌───────┬──────────┐
        │ top_k ┆ bottom_k │
        │ ---   ┆ ---      │
        │ i64   ┆ i64      │
        ╞═══════╪══════════╡
        │ 99    ┆ 1        │
        │ 98    ┆ 2        │
        │ 4     ┆ 3        │
        │ 3     ┆ 4        │
        │ 2     ┆ 98       │
        └───────┴──────────┘

        """
        k = parse_as_expression(k)
        return self._from_pyexpr(self._pyexpr.top_k(k))

    def bottom_k(self, k: int | IntoExprColumn = 5) -> Self:
        r"""
        Return the `k` smallest elements.

        This has time complexity:

        .. math:: O(n + k \\log{}n - \frac{k}{2})

        Parameters
        ----------
        k
            Number of elements to return.

        See Also
        --------
        top_k

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "value": [1, 98, 2, 3, 99, 4],
        ...     }
        ... )
        >>> df.select(
        ...     [
        ...         pl.col("value").top_k().alias("top_k"),
        ...         pl.col("value").bottom_k().alias("bottom_k"),
        ...     ]
        ... )
        shape: (5, 2)
        ┌───────┬──────────┐
        │ top_k ┆ bottom_k │
        │ ---   ┆ ---      │
        │ i64   ┆ i64      │
        ╞═══════╪══════════╡
        │ 99    ┆ 1        │
        │ 98    ┆ 2        │
        │ 4     ┆ 3        │
        │ 3     ┆ 4        │
        │ 2     ┆ 98       │
        └───────┴──────────┘

        """
        k = parse_as_expression(k)
        return self._from_pyexpr(self._pyexpr.bottom_k(k))

    def arg_sort(self, *, descending: bool = False, nulls_last: bool = False) -> Self:
        """
        Get the index values that would sort this column.

        Parameters
        ----------
        descending
            Sort in descending (descending) order.
        nulls_last
            Place null values last instead of first.

        Returns
        -------
        Expr
            Expression of data type :class:`UInt32`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [20, 10, 30],
        ...     }
        ... )
        >>> df.select(pl.col("a").arg_sort())
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 1   │
        │ 0   │
        │ 2   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arg_sort(descending, nulls_last))

    def arg_max(self) -> Self:
        """
        Get the index of the maximal value.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [20, 10, 30],
        ...     }
        ... )
        >>> df.select(pl.col("a").arg_max())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 2   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arg_max())

    def arg_min(self) -> Self:
        """
        Get the index of the minimal value.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [20, 10, 30],
        ...     }
        ... )
        >>> df.select(pl.col("a").arg_min())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 1   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arg_min())

    def search_sorted(self, element: IntoExpr, side: SearchSortedSide = "any") -> Self:
        """
        Find indices where elements should be inserted to maintain order.

        .. math:: a[i-1] < v <= a[i]

        Parameters
        ----------
        element
            Expression or scalar value.
        side : {'any', 'left', 'right'}
            If 'any', the index of the first suitable location found is given.
            If 'left', the index of the leftmost suitable location found is given.
            If 'right', return the rightmost suitable location found is given.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "values": [1, 2, 3, 5],
        ...     }
        ... )
        >>> df.select(
        ...     [
        ...         pl.col("values").search_sorted(0).alias("zero"),
        ...         pl.col("values").search_sorted(3).alias("three"),
        ...         pl.col("values").search_sorted(6).alias("six"),
        ...     ]
        ... )
        shape: (1, 3)
        ┌──────┬───────┬─────┐
        │ zero ┆ three ┆ six │
        │ ---  ┆ ---   ┆ --- │
        │ u32  ┆ u32   ┆ u32 │
        ╞══════╪═══════╪═════╡
        │ 0    ┆ 2     ┆ 4   │
        └──────┴───────┴─────┘

        """
        element = parse_as_expression(element)
        return self._from_pyexpr(self._pyexpr.search_sorted(element, side))

    def sort_by(
        self,
        by: IntoExpr | Iterable[IntoExpr],
        *more_by: IntoExpr,
        descending: bool | Sequence[bool] = False,
    ) -> Self:
        """
        Sort this column by the ordering of other columns.

        When used in a projection/selection context, the whole column is sorted.
        When used in a group by context, the groups are sorted.

        Parameters
        ----------
        by
            Column(s) to sort by. Accepts expression input. Strings are parsed as column
            names.
        *more_by
            Additional columns to sort by, specified as positional arguments.
        descending
            Sort in descending order. When sorting by multiple columns, can be specified
            per column by passing a sequence of booleans.

        Examples
        --------
        Pass a single column name to sort by that column.

        >>> df = pl.DataFrame(
        ...     {
        ...         "group": ["a", "a", "b", "b"],
        ...         "value1": [1, 3, 4, 2],
        ...         "value2": [8, 7, 6, 5],
        ...     }
        ... )
        >>> df.select(pl.col("group").sort_by("value1"))
        shape: (4, 1)
        ┌───────┐
        │ group │
        │ ---   │
        │ str   │
        ╞═══════╡
        │ a     │
        │ b     │
        │ a     │
        │ b     │
        └───────┘

        Sorting by expressions is also supported.

        >>> df.select(pl.col("group").sort_by(pl.col("value1") + pl.col("value2")))
        shape: (4, 1)
        ┌───────┐
        │ group │
        │ ---   │
        │ str   │
        ╞═══════╡
        │ b     │
        │ a     │
        │ a     │
        │ b     │
        └───────┘

        Sort by multiple columns by passing a list of columns.

        >>> df.select(pl.col("group").sort_by(["value1", "value2"], descending=True))
        shape: (4, 1)
        ┌───────┐
        │ group │
        │ ---   │
        │ str   │
        ╞═══════╡
        │ b     │
        │ a     │
        │ b     │
        │ a     │
        └───────┘

        Or use positional arguments to sort by multiple columns in the same way.

        >>> df.select(pl.col("group").sort_by("value1", "value2"))
        shape: (4, 1)
        ┌───────┐
        │ group │
        │ ---   │
        │ str   │
        ╞═══════╡
        │ a     │
        │ b     │
        │ a     │
        │ b     │
        └───────┘

        When sorting in a group by context, the groups are sorted.

        >>> df.group_by("group").agg(
        ...     pl.col("value1").sort_by("value2")
        ... )  # doctest: +IGNORE_RESULT
        shape: (2, 2)
        ┌───────┬───────────┐
        │ group ┆ value1    │
        │ ---   ┆ ---       │
        │ str   ┆ list[i64] │
        ╞═══════╪═══════════╡
        │ a     ┆ [3, 1]    │
        │ b     ┆ [2, 4]    │
        └───────┴───────────┘

        Take a single row from each group where a column attains its minimal value
        within that group.

        >>> df.group_by("group").agg(
        ...     pl.all().sort_by("value2").first()
        ... )  # doctest: +IGNORE_RESULT
        shape: (2, 3)
        ┌───────┬────────┬────────┐
        │ group ┆ value1 ┆ value2 |
        │ ---   ┆ ---    ┆ ---    │
        │ str   ┆ i64    ┆ i64    |
        ╞═══════╪════════╪════════╡
        │ a     ┆ 3      ┆ 7      |
        │ b     ┆ 2      ┆ 5      |
        └───────┴────────┴────────┘

        """
        by = parse_as_list_of_expressions(by, *more_by)
        if isinstance(descending, bool):
            descending = [descending]
        elif len(by) != len(descending):
            raise ValueError(
                f"the length of `descending` ({len(descending)}) does not match the length of `by` ({len(by)})"
            )
        return self._from_pyexpr(self._pyexpr.sort_by(by, descending))

    def gather(
        self, indices: int | list[int] | Expr | Series | np.ndarray[Any, Any]
    ) -> Self:
        """
        Take values by index.

        Parameters
        ----------
        indices
            An expression that leads to a UInt32 dtyped Series.

        Returns
        -------
        Expr
            Expression of the same data type.

        See Also
        --------
        Expr.get : Take a single value

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group": [
        ...             "one",
        ...             "one",
        ...             "one",
        ...             "two",
        ...             "two",
        ...             "two",
        ...         ],
        ...         "value": [1, 98, 2, 3, 99, 4],
        ...     }
        ... )
        >>> df.group_by("group", maintain_order=True).agg(
        ...     pl.col("value").gather([2, 1])
        ... )
        shape: (2, 2)
        ┌───────┬───────────┐
        │ group ┆ value     │
        │ ---   ┆ ---       │
        │ str   ┆ list[i64] │
        ╞═══════╪═══════════╡
        │ one   ┆ [2, 98]   │
        │ two   ┆ [4, 99]   │
        └───────┴───────────┘
        """
        if isinstance(indices, list) or (
            _check_for_numpy(indices) and isinstance(indices, np.ndarray)
        ):
            indices_lit = F.lit(pl.Series("", indices, dtype=UInt32))._pyexpr
        else:
            indices_lit = parse_as_expression(indices)
        return self._from_pyexpr(self._pyexpr.gather(indices_lit))

    def get(self, index: int | Expr) -> Self:
        """
        Return a single value by index.

        Parameters
        ----------
        index
            An expression that leads to a UInt32 index.

        Returns
        -------
        Expr
            Expression of the same data type.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group": [
        ...             "one",
        ...             "one",
        ...             "one",
        ...             "two",
        ...             "two",
        ...             "two",
        ...         ],
        ...         "value": [1, 98, 2, 3, 99, 4],
        ...     }
        ... )
        >>> df.group_by("group", maintain_order=True).agg(pl.col("value").get(1))
        shape: (2, 2)
        ┌───────┬───────┐
        │ group ┆ value │
        │ ---   ┆ ---   │
        │ str   ┆ i64   │
        ╞═══════╪═══════╡
        │ one   ┆ 98    │
        │ two   ┆ 99    │
        └───────┴───────┘

        """
        index_lit = parse_as_expression(index)
        return self._from_pyexpr(self._pyexpr.get(index_lit))

    @deprecate_renamed_parameter("periods", "n", version="0.19.11")
    def shift(
        self, n: int | IntoExprColumn = 1, *, fill_value: IntoExpr | None = None
    ) -> Self:
        """
        Shift values by the given number of indices.

        Parameters
        ----------
        n
            Number of indices to shift forward. If a negative value is passed, values
            are shifted in the opposite direction instead.
        fill_value
            Fill the resulting null values with this value.

        Notes
        -----
        This method is similar to the `LAG` operation in SQL when the value for `n`
        is positive. With a negative value for `n`, it is similar to `LEAD`.

        Examples
        --------
        By default, values are shifted forward by one index.

        >>> df = pl.DataFrame({"a": [1, 2, 3, 4]})
        >>> df.with_columns(shift=pl.col("a").shift())
        shape: (4, 2)
        ┌─────┬───────┐
        │ a   ┆ shift │
        │ --- ┆ ---   │
        │ i64 ┆ i64   │
        ╞═════╪═══════╡
        │ 1   ┆ null  │
        │ 2   ┆ 1     │
        │ 3   ┆ 2     │
        │ 4   ┆ 3     │
        └─────┴───────┘

        Pass a negative value to shift in the opposite direction instead.

        >>> df.with_columns(shift=pl.col("a").shift(-2))
        shape: (4, 2)
        ┌─────┬───────┐
        │ a   ┆ shift │
        │ --- ┆ ---   │
        │ i64 ┆ i64   │
        ╞═════╪═══════╡
        │ 1   ┆ 3     │
        │ 2   ┆ 4     │
        │ 3   ┆ null  │
        │ 4   ┆ null  │
        └─────┴───────┘

        Specify `fill_value` to fill the resulting null values.

        >>> df.with_columns(shift=pl.col("a").shift(-2, fill_value=100))
        shape: (4, 2)
        ┌─────┬───────┐
        │ a   ┆ shift │
        │ --- ┆ ---   │
        │ i64 ┆ i64   │
        ╞═════╪═══════╡
        │ 1   ┆ 3     │
        │ 2   ┆ 4     │
        │ 3   ┆ 100   │
        │ 4   ┆ 100   │
        └─────┴───────┘

        """
        if fill_value is not None:
            fill_value = parse_as_expression(fill_value, str_as_lit=True)
        n = parse_as_expression(n)
        return self._from_pyexpr(self._pyexpr.shift(n, fill_value))

    def fill_null(
        self,
        value: Any | None = None,
        strategy: FillNullStrategy | None = None,
        limit: int | None = None,
    ) -> Self:
        """
        Fill null values using the specified value or strategy.

        To interpolate over null values see interpolate.
        See the examples below to fill nulls with an expression.

        Parameters
        ----------
        value
            Value used to fill null values.
        strategy : {None, 'forward', 'backward', 'min', 'max', 'mean', 'zero', 'one'}
            Strategy used to fill null values.
        limit
            Number of consecutive null values to fill when using the 'forward' or
            'backward' strategy.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None],
        ...         "b": [4, None, 6],
        ...     }
        ... )
        >>> df.with_columns(pl.col("b").fill_null(strategy="zero"))
        shape: (3, 2)
        ┌──────┬─────┐
        │ a    ┆ b   │
        │ ---  ┆ --- │
        │ i64  ┆ i64 │
        ╞══════╪═════╡
        │ 1    ┆ 4   │
        │ 2    ┆ 0   │
        │ null ┆ 6   │
        └──────┴─────┘
        >>> df.with_columns(pl.col("b").fill_null(99))
        shape: (3, 2)
        ┌──────┬─────┐
        │ a    ┆ b   │
        │ ---  ┆ --- │
        │ i64  ┆ i64 │
        ╞══════╪═════╡
        │ 1    ┆ 4   │
        │ 2    ┆ 99  │
        │ null ┆ 6   │
        └──────┴─────┘
        >>> df.with_columns(pl.col("b").fill_null(strategy="forward"))
        shape: (3, 2)
        ┌──────┬─────┐
        │ a    ┆ b   │
        │ ---  ┆ --- │
        │ i64  ┆ i64 │
        ╞══════╪═════╡
        │ 1    ┆ 4   │
        │ 2    ┆ 4   │
        │ null ┆ 6   │
        └──────┴─────┘
        >>> df.with_columns(pl.col("b").fill_null(pl.col("b").median()))
        shape: (3, 2)
        ┌──────┬─────┐
        │ a    ┆ b   │
        │ ---  ┆ --- │
        │ i64  ┆ f64 │
        ╞══════╪═════╡
        │ 1    ┆ 4.0 │
        │ 2    ┆ 5.0 │
        │ null ┆ 6.0 │
        └──────┴─────┘
        >>> df.with_columns(pl.all().fill_null(pl.all().median()))
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ f64 ┆ f64 │
        ╞═════╪═════╡
        │ 1.0 ┆ 4.0 │
        │ 2.0 ┆ 5.0 │
        │ 1.5 ┆ 6.0 │
        └─────┴─────┘

        """
        if value is not None and strategy is not None:
            raise ValueError("cannot specify both `value` and `strategy`")
        elif value is None and strategy is None:
            raise ValueError("must specify either a fill `value` or `strategy`")
        elif strategy not in ("forward", "backward") and limit is not None:
            raise ValueError(
                "can only specify `limit` when strategy is set to 'backward' or 'forward'"
            )

        if value is not None:
            value = parse_as_expression(value, str_as_lit=True)
            return self._from_pyexpr(self._pyexpr.fill_null(value))
        else:
            return self._from_pyexpr(
                self._pyexpr.fill_null_with_strategy(strategy, limit)
            )

    def fill_nan(self, value: int | float | Expr | None) -> Self:
        """
        Fill floating point NaN value with a fill value.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1.0, None, float("nan")],
        ...         "b": [4.0, float("nan"), 6],
        ...     }
        ... )
        >>> df.with_columns(pl.col("b").fill_nan(0))
        shape: (3, 2)
        ┌──────┬─────┐
        │ a    ┆ b   │
        │ ---  ┆ --- │
        │ f64  ┆ f64 │
        ╞══════╪═════╡
        │ 1.0  ┆ 4.0 │
        │ null ┆ 0.0 │
        │ NaN  ┆ 6.0 │
        └──────┴─────┘

        """
        fill_value = parse_as_expression(value, str_as_lit=True)
        return self._from_pyexpr(self._pyexpr.fill_nan(fill_value))

    def forward_fill(self, limit: int | None = None) -> Self:
        """
        Fill missing values with the latest seen values.

        Parameters
        ----------
        limit
            The number of consecutive null values to forward fill.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None],
        ...         "b": [4, None, 6],
        ...     }
        ... )
        >>> df.select(pl.all().forward_fill())
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 1   ┆ 4   │
        │ 2   ┆ 4   │
        │ 2   ┆ 6   │
        └─────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.forward_fill(limit))

    def backward_fill(self, limit: int | None = None) -> Self:
        """
        Fill missing values with the next to be seen values.

        Parameters
        ----------
        limit
            The number of consecutive null values to backward fill.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None],
        ...         "b": [4, None, 6],
        ...         "c": [None, None, 2],
        ...     }
        ... )
        >>> df.select(pl.all().backward_fill())
        shape: (3, 3)
        ┌──────┬─────┬─────┐
        │ a    ┆ b   ┆ c   │
        │ ---  ┆ --- ┆ --- │
        │ i64  ┆ i64 ┆ i64 │
        ╞══════╪═════╪═════╡
        │ 1    ┆ 4   ┆ 2   │
        │ 2    ┆ 6   ┆ 2   │
        │ null ┆ 6   ┆ 2   │
        └──────┴─────┴─────┘
        >>> df.select(pl.all().backward_fill(limit=1))
        shape: (3, 3)
        ┌──────┬─────┬──────┐
        │ a    ┆ b   ┆ c    │
        │ ---  ┆ --- ┆ ---  │
        │ i64  ┆ i64 ┆ i64  │
        ╞══════╪═════╪══════╡
        │ 1    ┆ 4   ┆ null │
        │ 2    ┆ 6   ┆ 2    │
        │ null ┆ 6   ┆ 2    │
        └──────┴─────┴──────┘

        """
        return self._from_pyexpr(self._pyexpr.backward_fill(limit))

    def reverse(self) -> Self:
        """
        Reverse the selection.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "A": [1, 2, 3, 4, 5],
        ...         "fruits": ["banana", "banana", "apple", "apple", "banana"],
        ...         "B": [5, 4, 3, 2, 1],
        ...         "cars": ["beetle", "audi", "beetle", "beetle", "beetle"],
        ...     }
        ... )
        >>> df.select(
        ...     [
        ...         pl.all(),
        ...         pl.all().reverse().name.suffix("_reverse"),
        ...     ]
        ... )
        shape: (5, 8)
        ┌─────┬────────┬─────┬────────┬───────────┬────────────────┬───────────┬──────────────┐
        │ A   ┆ fruits ┆ B   ┆ cars   ┆ A_reverse ┆ fruits_reverse ┆ B_reverse ┆ cars_reverse │
        │ --- ┆ ---    ┆ --- ┆ ---    ┆ ---       ┆ ---            ┆ ---       ┆ ---          │
        │ i64 ┆ str    ┆ i64 ┆ str    ┆ i64       ┆ str            ┆ i64       ┆ str          │
        ╞═════╪════════╪═════╪════════╪═══════════╪════════════════╪═══════════╪══════════════╡
        │ 1   ┆ banana ┆ 5   ┆ beetle ┆ 5         ┆ banana         ┆ 1         ┆ beetle       │
        │ 2   ┆ banana ┆ 4   ┆ audi   ┆ 4         ┆ apple          ┆ 2         ┆ beetle       │
        │ 3   ┆ apple  ┆ 3   ┆ beetle ┆ 3         ┆ apple          ┆ 3         ┆ beetle       │
        │ 4   ┆ apple  ┆ 2   ┆ beetle ┆ 2         ┆ banana         ┆ 4         ┆ audi         │
        │ 5   ┆ banana ┆ 1   ┆ beetle ┆ 1         ┆ banana         ┆ 5         ┆ beetle       │
        └─────┴────────┴─────┴────────┴───────────┴────────────────┴───────────┴──────────────┘

        """  # noqa: W505
        return self._from_pyexpr(self._pyexpr.reverse())

    def std(self, ddof: int = 1) -> Self:
        """
        Get standard deviation.

        Parameters
        ----------
        ddof
            “Delta Degrees of Freedom”: the divisor used in the calculation is N - ddof,
            where N represents the number of elements.
            By default ddof is 1.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, 0, 1]})
        >>> df.select(pl.col("a").std())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.std(ddof))

    def var(self, ddof: int = 1) -> Self:
        """
        Get variance.

        Parameters
        ----------
        ddof
            “Delta Degrees of Freedom”: the divisor used in the calculation is N - ddof,
            where N represents the number of elements.
            By default ddof is 1.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, 0, 1]})
        >>> df.select(pl.col("a").var())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.var(ddof))

    def max(self) -> Self:
        """
        Get maximum value.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, float("nan"), 1]})
        >>> df.select(pl.col("a").max())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.max())

    def min(self) -> Self:
        """
        Get minimum value.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, float("nan"), 1]})
        >>> df.select(pl.col("a").min())
        shape: (1, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ -1.0 │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.min())

    def nan_max(self) -> Self:
        """
        Get maximum value, but propagate/poison encountered NaN values.

        This differs from numpy's `nanmax` as numpy defaults to propagating NaN values,
        whereas polars defaults to ignoring them.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0, float("nan")]})
        >>> df.select(pl.col("a").nan_max())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ NaN │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.nan_max())

    def nan_min(self) -> Self:
        """
        Get minimum value, but propagate/poison encountered NaN values.

        This differs from numpy's `nanmax` as numpy defaults to propagating NaN values,
        whereas polars defaults to ignoring them.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0, float("nan")]})
        >>> df.select(pl.col("a").nan_min())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ NaN │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.nan_min())

    def sum(self) -> Self:
        """
        Get sum value.

        Notes
        -----
        Dtypes in {Int8, UInt8, Int16, UInt16} are cast to
        Int64 before summing to prevent overflow issues.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, 0, 1]})
        >>> df.select(pl.col("a").sum())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │  0  │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.sum())

    def mean(self) -> Self:
        """
        Get mean value.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, 0, 1]})
        >>> df.select(pl.col("a").mean())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.mean())

    def median(self) -> Self:
        """
        Get median value using linear interpolation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-1, 0, 1]})
        >>> df.select(pl.col("a").median())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.median())

    def product(self) -> Self:
        """
        Compute the product of an expression.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").product())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 6   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.product())

    def n_unique(self) -> Self:
        """
        Count unique values.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").n_unique())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 2   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.n_unique())

    def approx_n_unique(self) -> Self:
        """
        Approximate count of unique values.

        This is done using the HyperLogLog++ algorithm for cardinality estimation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").approx_n_unique())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 2   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.approx_n_unique())

    def null_count(self) -> Self:
        """
        Count null values.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [None, 1, None],
        ...         "b": [1, 2, 3],
        ...     }
        ... )
        >>> df.select(pl.all().null_count())
        shape: (1, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ u32 ┆ u32 │
        ╞═════╪═════╡
        │ 2   ┆ 0   │
        └─────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.null_count())

    def arg_unique(self) -> Self:
        """
        Get index of first unique value.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [8, 9, 10],
        ...         "b": [None, 4, 4],
        ...     }
        ... )
        >>> df.select(pl.col("a").arg_unique())
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 0   │
        │ 1   │
        │ 2   │
        └─────┘
        >>> df.select(pl.col("b").arg_unique())
        shape: (2, 1)
        ┌─────┐
        │ b   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 0   │
        │ 1   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arg_unique())

    def unique(self, *, maintain_order: bool = False) -> Self:
        """
        Get unique values of this expression.

        Parameters
        ----------
        maintain_order
            Maintain order of data. This requires more work.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").unique())  # doctest: +IGNORE_RESULT
        shape: (2, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 2   │
        │ 1   │
        └─────┘
        >>> df.select(pl.col("a").unique(maintain_order=True))
        shape: (2, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        │ 2   │
        └─────┘

        """
        if maintain_order:
            return self._from_pyexpr(self._pyexpr.unique_stable())
        return self._from_pyexpr(self._pyexpr.unique())

    def first(self) -> Self:
        """
        Get the first value.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").first())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.first())

    def last(self) -> Self:
        """
        Get the last value.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").last())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 2   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.last())

    def over(
        self,
        expr: IntoExpr | Iterable[IntoExpr],
        *more_exprs: IntoExpr,
        mapping_strategy: WindowMappingStrategy = "group_to_rows",
    ) -> Self:
        """
        Compute expressions over the given groups.

        This expression is similar to performing a group by aggregation and joining the
        result back into the original DataFrame.

        The outcome is similar to how `window functions
        <https://www.postgresql.org/docs/current/tutorial-window.html>`_
        work in PostgreSQL.

        Parameters
        ----------
        expr
            Column(s) to group by. Accepts expression input. Strings are parsed as
            column names.
        *more_exprs
            Additional columns to group by, specified as positional arguments.
        mapping_strategy: {'group_to_rows', 'join', 'explode'}
            - group_to_rows
                If the aggregation results in multiple values, assign them back to their
                position in the DataFrame. This can only be done if the group yields
                the same elements before aggregation as after.
            - join
                Join the groups as 'List<group_dtype>' to the row positions.
                warning: this can be memory intensive.
            - explode
                Don't do any mapping, but simply flatten the group.
                This only makes sense if the input data is sorted.

        Examples
        --------
        Pass the name of a column to compute the expression over that column.

        >>> df = pl.DataFrame(
        ...     {
        ...         "a": ["a", "a", "b", "b", "b"],
        ...         "b": [1, 2, 3, 5, 3],
        ...         "c": [5, 4, 3, 2, 1],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("c").max().over("a").name.suffix("_max"),
        ... )
        shape: (5, 4)
        ┌─────┬─────┬─────┬───────┐
        │ a   ┆ b   ┆ c   ┆ c_max │
        │ --- ┆ --- ┆ --- ┆ ---   │
        │ str ┆ i64 ┆ i64 ┆ i64   │
        ╞═════╪═════╪═════╪═══════╡
        │ a   ┆ 1   ┆ 5   ┆ 5     │
        │ a   ┆ 2   ┆ 4   ┆ 5     │
        │ b   ┆ 3   ┆ 3   ┆ 3     │
        │ b   ┆ 5   ┆ 2   ┆ 3     │
        │ b   ┆ 3   ┆ 1   ┆ 3     │
        └─────┴─────┴─────┴───────┘

        Expression input is supported.

        >>> df.with_columns(
        ...     pl.col("c").max().over(pl.col("b") // 2).name.suffix("_max"),
        ... )
        shape: (5, 4)
        ┌─────┬─────┬─────┬───────┐
        │ a   ┆ b   ┆ c   ┆ c_max │
        │ --- ┆ --- ┆ --- ┆ ---   │
        │ str ┆ i64 ┆ i64 ┆ i64   │
        ╞═════╪═════╪═════╪═══════╡
        │ a   ┆ 1   ┆ 5   ┆ 5     │
        │ a   ┆ 2   ┆ 4   ┆ 4     │
        │ b   ┆ 3   ┆ 3   ┆ 4     │
        │ b   ┆ 5   ┆ 2   ┆ 2     │
        │ b   ┆ 3   ┆ 1   ┆ 4     │
        └─────┴─────┴─────┴───────┘

        Group by multiple columns by passing a list of column names or expressions.

        >>> df.with_columns(
        ...     pl.col("c").min().over(["a", "b"]).name.suffix("_min"),
        ... )
        shape: (5, 4)
        ┌─────┬─────┬─────┬───────┐
        │ a   ┆ b   ┆ c   ┆ c_min │
        │ --- ┆ --- ┆ --- ┆ ---   │
        │ str ┆ i64 ┆ i64 ┆ i64   │
        ╞═════╪═════╪═════╪═══════╡
        │ a   ┆ 1   ┆ 5   ┆ 5     │
        │ a   ┆ 2   ┆ 4   ┆ 4     │
        │ b   ┆ 3   ┆ 3   ┆ 1     │
        │ b   ┆ 5   ┆ 2   ┆ 2     │
        │ b   ┆ 3   ┆ 1   ┆ 1     │
        └─────┴─────┴─────┴───────┘

        Or use positional arguments to group by multiple columns in the same way.

        >>> df.with_columns(
        ...     pl.col("c").min().over("a", pl.col("b") % 2).name.suffix("_min"),
        ... )
        shape: (5, 4)
        ┌─────┬─────┬─────┬───────┐
        │ a   ┆ b   ┆ c   ┆ c_min │
        │ --- ┆ --- ┆ --- ┆ ---   │
        │ str ┆ i64 ┆ i64 ┆ i64   │
        ╞═════╪═════╪═════╪═══════╡
        │ a   ┆ 1   ┆ 5   ┆ 5     │
        │ a   ┆ 2   ┆ 4   ┆ 4     │
        │ b   ┆ 3   ┆ 3   ┆ 1     │
        │ b   ┆ 5   ┆ 2   ┆ 1     │
        │ b   ┆ 3   ┆ 1   ┆ 1     │
        └─────┴─────┴─────┴───────┘

        """
        exprs = parse_as_list_of_expressions(expr, *more_exprs)
        return self._from_pyexpr(self._pyexpr.over(exprs, mapping_strategy))

    def rolling(
        self,
        index_column: str,
        *,
        period: str | timedelta,
        offset: str | timedelta | None = None,
        closed: ClosedInterval = "right",
        check_sorted: bool = True,
    ) -> Self:
        """
        Create rolling groups based on a time, Int32, or Int64 column.

        If you have a time series `<t_0, t_1, ..., t_n>`, then by default the
        windows created will be

            * (t_0 - period, t_0]
            * (t_1 - period, t_1]
            * ...
            * (t_n - period, t_n]

        whereas if you pass a non-default `offset`, then the windows will be

            * (t_0 + offset, t_0 + offset + period]
            * (t_1 + offset, t_1 + offset + period]
            * ...
            * (t_n + offset, t_n + offset + period]

        The `period` and `offset` arguments are created either from a timedelta, or
        by using the following string language:

        - 1ns   (1 nanosecond)
        - 1us   (1 microsecond)
        - 1ms   (1 millisecond)
        - 1s    (1 second)
        - 1m    (1 minute)
        - 1h    (1 hour)
        - 1d    (1 calendar day)
        - 1w    (1 calendar week)
        - 1mo   (1 calendar month)
        - 1q    (1 calendar quarter)
        - 1y    (1 calendar year)
        - 1i    (1 index count)

        Or combine them:
        "3d12h4m25s" # 3 days, 12 hours, 4 minutes, and 25 seconds

        By "calendar day", we mean the corresponding time on the next day (which may
        not be 24 hours, due to daylight savings). Similarly for "calendar week",
        "calendar month", "calendar quarter", and "calendar year".

        In case of a rolling operation on an integer column, the windows are defined by:

        - "1i"      # length 1
        - "10i"     # length 10

        Parameters
        ----------
        index_column
            Column used to group based on the time window.
            Often of type Date/Datetime.
            This column must be sorted in ascending order.
            In case of a rolling group by on indices, dtype needs to be one of
            {Int32, Int64}. Note that Int32 gets temporarily cast to Int64, so if
            performance matters use an Int64 column.
        period
            length of the window - must be non-negative
        offset
            offset of the window. Default is -period
        closed : {'right', 'left', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive).
        check_sorted
            When the `by` argument is given, polars can not check sortedness
            by the metadata and has to do a full scan on the index column to
            verify data is sorted. This is expensive. If you are sure the
            data within the by groups is sorted, you can set this to `False`.
            Doing so incorrectly will lead to incorrect output

        Examples
        --------
        >>> dates = [
        ...     "2020-01-01 13:45:48",
        ...     "2020-01-01 16:42:13",
        ...     "2020-01-01 16:45:09",
        ...     "2020-01-02 18:12:48",
        ...     "2020-01-03 19:45:32",
        ...     "2020-01-08 23:16:43",
        ... ]
        >>> df = pl.DataFrame({"dt": dates, "a": [3, 7, 5, 9, 2, 1]}).with_columns(
        ...     pl.col("dt").str.strptime(pl.Datetime).set_sorted()
        ... )
        >>> df.with_columns(
        ...     sum_a=pl.sum("a").rolling(index_column="dt", period="2d"),
        ...     min_a=pl.min("a").rolling(index_column="dt", period="2d"),
        ...     max_a=pl.max("a").rolling(index_column="dt", period="2d"),
        ... )
        shape: (6, 5)
        ┌─────────────────────┬─────┬───────┬───────┬───────┐
        │ dt                  ┆ a   ┆ sum_a ┆ min_a ┆ max_a │
        │ ---                 ┆ --- ┆ ---   ┆ ---   ┆ ---   │
        │ datetime[μs]        ┆ i64 ┆ i64   ┆ i64   ┆ i64   │
        ╞═════════════════════╪═════╪═══════╪═══════╪═══════╡
        │ 2020-01-01 13:45:48 ┆ 3   ┆ 3     ┆ 3     ┆ 3     │
        │ 2020-01-01 16:42:13 ┆ 7   ┆ 10    ┆ 3     ┆ 7     │
        │ 2020-01-01 16:45:09 ┆ 5   ┆ 15    ┆ 3     ┆ 7     │
        │ 2020-01-02 18:12:48 ┆ 9   ┆ 24    ┆ 3     ┆ 9     │
        │ 2020-01-03 19:45:32 ┆ 2   ┆ 11    ┆ 2     ┆ 9     │
        │ 2020-01-08 23:16:43 ┆ 1   ┆ 1     ┆ 1     ┆ 1     │
        └─────────────────────┴─────┴───────┴───────┴───────┘

        """
        period = deprecate_saturating(period)
        offset = deprecate_saturating(offset)
        if offset is None:
            offset = _negate_duration(_timedelta_to_pl_duration(period))

        period = _timedelta_to_pl_duration(period)
        offset = _timedelta_to_pl_duration(offset)

        return self._from_pyexpr(
            self._pyexpr.rolling(index_column, period, offset, closed, check_sorted)
        )

    def is_unique(self) -> Self:
        """
        Get mask of unique values.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").is_unique())
        shape: (3, 1)
        ┌───────┐
        │ a     │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ false │
        │ false │
        │ true  │
        └───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_unique())

    def is_first_distinct(self) -> Self:
        """
        Return a boolean mask indicating the first occurrence of each distinct value.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2, 3, 2]})
        >>> df.with_columns(pl.col("a").is_first_distinct().alias("first"))
        shape: (5, 2)
        ┌─────┬───────┐
        │ a   ┆ first │
        │ --- ┆ ---   │
        │ i64 ┆ bool  │
        ╞═════╪═══════╡
        │ 1   ┆ true  │
        │ 1   ┆ false │
        │ 2   ┆ true  │
        │ 3   ┆ true  │
        │ 2   ┆ false │
        └─────┴───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_first_distinct())

    def is_last_distinct(self) -> Self:
        """
        Return a boolean mask indicating the last occurrence of each distinct value.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2, 3, 2]})
        >>> df.with_columns(pl.col("a").is_last_distinct().alias("last"))
        shape: (5, 2)
        ┌─────┬───────┐
        │ a   ┆ last  │
        │ --- ┆ ---   │
        │ i64 ┆ bool  │
        ╞═════╪═══════╡
        │ 1   ┆ false │
        │ 1   ┆ true  │
        │ 2   ┆ false │
        │ 3   ┆ true  │
        │ 2   ┆ true  │
        └─────┴───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_last_distinct())

    def is_duplicated(self) -> Self:
        """
        Return a boolean mask indicating duplicated values.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 1, 2]})
        >>> df.select(pl.col("a").is_duplicated())
        shape: (3, 1)
        ┌───────┐
        │ a     │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ true  │
        │ true  │
        │ false │
        └───────┘

        """
        return self._from_pyexpr(self._pyexpr.is_duplicated())

    def peak_max(self) -> Self:
        """
        Get a boolean mask of the local maximum peaks.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 4, 5]})
        >>> df.select(pl.col("a").peak_max())
        shape: (5, 1)
        ┌───────┐
        │ a     │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ false │
        │ false │
        │ false │
        │ false │
        │ true  │
        └───────┘

        """
        return self._from_pyexpr(self._pyexpr.peak_max())

    def peak_min(self) -> Self:
        """
        Get a boolean mask of the local minimum peaks.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [4, 1, 3, 2, 5]})
        >>> df.select(pl.col("a").peak_min())
        shape: (5, 1)
        ┌───────┐
        │ a     │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ false │
        │ true  │
        │ false │
        │ true  │
        │ false │
        └───────┘

        """
        return self._from_pyexpr(self._pyexpr.peak_min())

    def quantile(
        self,
        quantile: float | Expr,
        interpolation: RollingInterpolationMethod = "nearest",
    ) -> Self:
        """
        Get quantile value.

        Parameters
        ----------
        quantile
            Quantile between 0.0 and 1.0.
        interpolation : {'nearest', 'higher', 'lower', 'midpoint', 'linear'}
            Interpolation method.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0, 1, 2, 3, 4, 5]})
        >>> df.select(pl.col("a").quantile(0.3))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘
        >>> df.select(pl.col("a").quantile(0.3, interpolation="higher"))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 2.0 │
        └─────┘
        >>> df.select(pl.col("a").quantile(0.3, interpolation="lower"))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘
        >>> df.select(pl.col("a").quantile(0.3, interpolation="midpoint"))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.5 │
        └─────┘
        >>> df.select(pl.col("a").quantile(0.3, interpolation="linear"))
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.5 │
        └─────┘

        """
        quantile = parse_as_expression(quantile)
        return self._from_pyexpr(self._pyexpr.quantile(quantile, interpolation))

    @deprecate_nonkeyword_arguments(["self", "breaks"], version="0.18.14")
    def cut(
        self,
        breaks: Sequence[float],
        labels: Sequence[str] | None = None,
        left_closed: bool = False,  # noqa: FBT001
        include_breaks: bool = False,  # noqa: FBT001
    ) -> Self:
        """
        Bin continuous values into discrete categories.

        Parameters
        ----------
        breaks
            List of unique cut points.
        labels
            Names of the categories. The number of labels must be equal to the number
            of cut points plus one.
        left_closed
            Set the intervals to be left-closed instead of right-closed.
        include_breaks
            Include a column with the right endpoint of the bin each observation falls
            in. This will change the data type of the output from a
            :class:`Categorical` to a :class:`Struct`.

        Returns
        -------
        Expr
            Expression of data type :class:`Categorical` if `include_breaks` is set to
            `False` (default), otherwise an expression of data type :class:`Struct`.

        See Also
        --------
        qcut

        Examples
        --------
        Divide a column into three categories.

        >>> df = pl.DataFrame({"foo": [-2, -1, 0, 1, 2]})
        >>> df.with_columns(
        ...     pl.col("foo").cut([-1, 1], labels=["a", "b", "c"]).alias("cut")
        ... )
        shape: (5, 2)
        ┌─────┬─────┐
        │ foo ┆ cut │
        │ --- ┆ --- │
        │ i64 ┆ cat │
        ╞═════╪═════╡
        │ -2  ┆ a   │
        │ -1  ┆ a   │
        │ 0   ┆ b   │
        │ 1   ┆ b   │
        │ 2   ┆ c   │
        └─────┴─────┘

        Add both the category and the breakpoint.

        >>> df.with_columns(
        ...     pl.col("foo").cut([-1, 1], include_breaks=True).alias("cut")
        ... ).unnest("cut")
        shape: (5, 3)
        ┌─────┬──────┬────────────┐
        │ foo ┆ brk  ┆ foo_bin    │
        │ --- ┆ ---  ┆ ---        │
        │ i64 ┆ f64  ┆ cat        │
        ╞═════╪══════╪════════════╡
        │ -2  ┆ -1.0 ┆ (-inf, -1] │
        │ -1  ┆ -1.0 ┆ (-inf, -1] │
        │ 0   ┆ 1.0  ┆ (-1, 1]    │
        │ 1   ┆ 1.0  ┆ (-1, 1]    │
        │ 2   ┆ inf  ┆ (1, inf]   │
        └─────┴──────┴────────────┘

        """
        return self._from_pyexpr(
            self._pyexpr.cut(breaks, labels, left_closed, include_breaks)
        )

    @deprecate_nonkeyword_arguments(["self", "quantiles"], version="0.18.14")
    @deprecate_renamed_parameter("probs", "quantiles", version="0.18.8")
    @deprecate_renamed_parameter("q", "quantiles", version="0.18.12")
    def qcut(
        self,
        quantiles: Sequence[float] | int,
        labels: Sequence[str] | None = None,
        left_closed: bool = False,  # noqa: FBT001
        allow_duplicates: bool = False,  # noqa: FBT001
        include_breaks: bool = False,  # noqa: FBT001
    ) -> Self:
        """
        Bin continuous values into discrete categories based on their quantiles.

        Parameters
        ----------
        quantiles
            Either a list of quantile probabilities between 0 and 1 or a positive
            integer determining the number of bins with uniform probability.
        labels
            Names of the categories. The number of labels must be equal to the number
            of categories.
        left_closed
            Set the intervals to be left-closed instead of right-closed.
        allow_duplicates
            If set to `True`, duplicates in the resulting quantiles are dropped,
            rather than raising a `DuplicateError`. This can happen even with unique
            probabilities, depending on the data.
        include_breaks
            Include a column with the right endpoint of the bin each observation falls
            in. This will change the data type of the output from a
            :class:`Categorical` to a :class:`Struct`.

        Returns
        -------
        Expr
            Expression of data type :class:`Categorical` if `include_breaks` is set to
            `False` (default), otherwise an expression of data type :class:`Struct`.

        See Also
        --------
        cut

        Examples
        --------
        Divide a column into three categories according to pre-defined quantile
        probabilities.

        >>> df = pl.DataFrame({"foo": [-2, -1, 0, 1, 2]})
        >>> df.with_columns(
        ...     pl.col("foo").qcut([0.25, 0.75], labels=["a", "b", "c"]).alias("qcut")
        ... )
        shape: (5, 2)
        ┌─────┬──────┐
        │ foo ┆ qcut │
        │ --- ┆ ---  │
        │ i64 ┆ cat  │
        ╞═════╪══════╡
        │ -2  ┆ a    │
        │ -1  ┆ a    │
        │ 0   ┆ b    │
        │ 1   ┆ b    │
        │ 2   ┆ c    │
        └─────┴──────┘

        Divide a column into two categories using uniform quantile probabilities.

        >>> df.with_columns(
        ...     pl.col("foo")
        ...     .qcut(2, labels=["low", "high"], left_closed=True)
        ...     .alias("qcut")
        ... )
        shape: (5, 2)
        ┌─────┬──────┐
        │ foo ┆ qcut │
        │ --- ┆ ---  │
        │ i64 ┆ cat  │
        ╞═════╪══════╡
        │ -2  ┆ low  │
        │ -1  ┆ low  │
        │ 0   ┆ high │
        │ 1   ┆ high │
        │ 2   ┆ high │
        └─────┴──────┘

        Add both the category and the breakpoint.

        >>> df.with_columns(
        ...     pl.col("foo").qcut([0.25, 0.75], include_breaks=True).alias("qcut")
        ... ).unnest("qcut")
        shape: (5, 3)
        ┌─────┬──────┬────────────┐
        │ foo ┆ brk  ┆ foo_bin    │
        │ --- ┆ ---  ┆ ---        │
        │ i64 ┆ f64  ┆ cat        │
        ╞═════╪══════╪════════════╡
        │ -2  ┆ -1.0 ┆ (-inf, -1] │
        │ -1  ┆ -1.0 ┆ (-inf, -1] │
        │ 0   ┆ 1.0  ┆ (-1, 1]    │
        │ 1   ┆ 1.0  ┆ (-1, 1]    │
        │ 2   ┆ inf  ┆ (1, inf]   │
        └─────┴──────┴────────────┘

        """
        if isinstance(quantiles, int):
            pyexpr = self._pyexpr.qcut_uniform(
                quantiles, labels, left_closed, allow_duplicates, include_breaks
            )
        else:
            pyexpr = self._pyexpr.qcut(
                quantiles, labels, left_closed, allow_duplicates, include_breaks
            )

        return self._from_pyexpr(pyexpr)

    def rle(self) -> Self:
        """
        Get the lengths of runs of identical values.

        Returns
        -------
        Expr
            Expression of data type :class:`Struct` with Fields "lengths" and "values".

        Examples
        --------
        >>> df = pl.DataFrame(pl.Series("s", [1, 1, 2, 1, None, 1, 3, 3]))
        >>> df.select(pl.col("s").rle()).unnest("s")
        shape: (6, 2)
        ┌─────────┬────────┐
        │ lengths ┆ values │
        │ ---     ┆ ---    │
        │ i32     ┆ i64    │
        ╞═════════╪════════╡
        │ 2       ┆ 1      │
        │ 1       ┆ 2      │
        │ 1       ┆ 1      │
        │ 1       ┆ null   │
        │ 1       ┆ 1      │
        │ 2       ┆ 3      │
        └─────────┴────────┘
        """
        return self._from_pyexpr(self._pyexpr.rle())

    def rle_id(self) -> Self:
        """
        Map values to run IDs.

        Similar to RLE, but it maps each value to an ID corresponding to the run into
        which it falls. This is especially useful when you want to define groups by
        runs of identical values rather than the values themselves.


        Examples
        --------
        >>> df = pl.DataFrame(dict(a=[1, 2, 1, 1, 1], b=["x", "x", None, "y", "y"]))
        >>> # It works on structs of multiple values too!
        >>> df.with_columns(a_r=pl.col("a").rle_id(), ab_r=pl.struct("a", "b").rle_id())
        shape: (5, 4)
        ┌─────┬──────┬─────┬──────┐
        │ a   ┆ b    ┆ a_r ┆ ab_r │
        │ --- ┆ ---  ┆ --- ┆ ---  │
        │ i64 ┆ str  ┆ u32 ┆ u32  │
        ╞═════╪══════╪═════╪══════╡
        │ 1   ┆ x    ┆ 0   ┆ 0    │
        │ 2   ┆ x    ┆ 1   ┆ 1    │
        │ 1   ┆ null ┆ 2   ┆ 2    │
        │ 1   ┆ y    ┆ 2   ┆ 3    │
        │ 1   ┆ y    ┆ 2   ┆ 3    │
        └─────┴──────┴─────┴──────┘
        """
        return self._from_pyexpr(self._pyexpr.rle_id())

    def filter(self, predicate: Expr) -> Self:
        """
        Filter a single column.

        The original order of the remaining elements is preserved.

        Mostly useful in an aggregation context. If you want to filter on a DataFrame
        level, use `LazyFrame.filter`.

        Parameters
        ----------
        predicate
            Boolean expression.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group_col": ["g1", "g1", "g2"],
        ...         "b": [1, 2, 3],
        ...     }
        ... )
        >>> df.group_by("group_col").agg(
        ...     lt=pl.col("b").filter(pl.col("b") < 2).sum(),
        ...     gte=pl.col("b").filter(pl.col("b") >= 2).sum(),
        ... ).sort("group_col")
        shape: (2, 3)
        ┌───────────┬─────┬─────┐
        │ group_col ┆ lt  ┆ gte │
        │ ---       ┆ --- ┆ --- │
        │ str       ┆ i64 ┆ i64 │
        ╞═══════════╪═════╪═════╡
        │ g1        ┆ 1   ┆ 2   │
        │ g2        ┆ 0   ┆ 3   │
        └───────────┴─────┴─────┘

        """
        return self._from_pyexpr(self._pyexpr.filter(predicate._pyexpr))

    def where(self, predicate: Expr) -> Self:
        """
        Filter a single column.

        Alias for :func:`filter`.

        Parameters
        ----------
        predicate
            Boolean expression.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group_col": ["g1", "g1", "g2"],
        ...         "b": [1, 2, 3],
        ...     }
        ... )
        >>> df.group_by("group_col").agg(
        ...     [
        ...         pl.col("b").where(pl.col("b") < 2).sum().alias("lt"),
        ...         pl.col("b").where(pl.col("b") >= 2).sum().alias("gte"),
        ...     ]
        ... ).sort("group_col")
        shape: (2, 3)
        ┌───────────┬─────┬─────┐
        │ group_col ┆ lt  ┆ gte │
        │ ---       ┆ --- ┆ --- │
        │ str       ┆ i64 ┆ i64 │
        ╞═══════════╪═════╪═════╡
        │ g1        ┆ 1   ┆ 2   │
        │ g2        ┆ 0   ┆ 3   │
        └───────────┴─────┴─────┘

        """
        return self.filter(predicate)

    def map_batches(
        self,
        function: Callable[[Series], Series | Any],
        return_dtype: PolarsDataType | None = None,
        *,
        agg_list: bool = False,
    ) -> Self:
        """
        Apply a custom python function to a whole Series or sequence of Series.

        The output of this custom function must be a Series. If you want to apply a
        custom function elementwise over single values, see :func:`map_elements`.
        A reasonable use case for `map` functions is transforming the values
        represented by an expression using a third-party library.

        Read more in `the book
        <https://pola-rs.github.io/polars/user-guide/expressions/user-defined-functions>`_.

        Parameters
        ----------
        function
            Lambda/function to apply.
        return_dtype
            Dtype of the output Series.
        agg_list
            Aggregate list.

        Notes
        -----
        If you are looking to map a function over a window function or group_by context,
        refer to func:`map_elements` instead.

        Warnings
        --------
        If `return_dtype` is not provided, this may lead to unexpected results.
        We allow this, but it is considered a bug in the user's query.

        See Also
        --------
        map_elements
        replace

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "sine": [0.0, 1.0, 0.0, -1.0],
        ...         "cosine": [1.0, 0.0, -1.0, 0.0],
        ...     }
        ... )
        >>> df.select(pl.all().map_batches(lambda x: x.to_numpy().argmax()))
        shape: (1, 2)
        ┌──────┬────────┐
        │ sine ┆ cosine │
        │ ---  ┆ ---    │
        │ i64  ┆ i64    │
        ╞══════╪════════╡
        │ 1    ┆ 0      │
        └──────┴────────┘

        """
        if return_dtype is not None:
            return_dtype = py_type_to_dtype(return_dtype)
        return self._from_pyexpr(
            self._pyexpr.map_batches(function, return_dtype, agg_list)
        )

    def map_elements(
        self,
        function: Callable[[Series], Series] | Callable[[Any], Any],
        return_dtype: PolarsDataType | None = None,
        *,
        skip_nulls: bool = True,
        pass_name: bool = False,
        strategy: MapElementsStrategy = "thread_local",
    ) -> Self:
        """
        Map a custom/user-defined function (UDF) to each element of a column.

        .. warning::
            This method is much slower than the native expressions API.
            Only use it if you cannot implement your logic otherwise.

        The UDF is applied to each element of a column. Note that, in a GroupBy
        context, the column will have been pre-aggregated and so each element
        will itself be a Series. Therefore, depending on the context,
        requirements for `function` differ:

        * Selection
            Expects `function` to be of type `Callable[[Any], Any]`.
            Applies a Python function to each individual value in the column.
        * GroupBy
            Expects `function` to be of type `Callable[[Series], Any]`.
            For each group, applies a Python function to the slice of the column
            corresponding to that group.

        Parameters
        ----------
        function
            Lambda/function to map.
        return_dtype
            Dtype of the output Series.
            If not set, the dtype will be `pl.Unknown`.
        skip_nulls
            Don't map the function over values that contain nulls (this is faster).
        pass_name
            Pass the Series name to the custom function (this is more expensive).
        strategy : {'thread_local', 'threading'}
            This functionality is considered experimental and may be removed/changed.

            - 'thread_local': run the python function on a single thread.
            - 'threading': run the python function on separate threads. Use with
              care as this can slow performance. This might only speed up
              your code if the amount of work per element is significant
              and the python function releases the GIL (e.g. via calling
              a c function)

        Notes
        -----
        * Using `map_elements` is strongly discouraged as you will be effectively
          running python "for" loops, which will be very slow. Wherever possible you
          should prefer the native expression API to achieve the best performance.

        * If your function is expensive and you don't want it to be called more than
          once for a given input, consider applying an `@lru_cache` decorator to it.
          If your data is suitable you may achieve *significant* speedups.

        * Window function application using `over` is considered a GroupBy context
          here, so `map_elements` can be used to map functions over window groups.

        Warnings
        --------
        If `return_dtype` is not provided, this may lead to unexpected results.
        We allow this, but it is considered a bug in the user's query.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3, 1],
        ...         "b": ["a", "b", "c", "c"],
        ...     }
        ... )

        The function is applied to each element of column `'a'`:

        >>> df.with_columns(  # doctest: +SKIP
        ...     pl.col("a").map_elements(lambda x: x * 2).alias("a_times_2"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬───────────┐
        │ a   ┆ b   ┆ a_times_2 │
        │ --- ┆ --- ┆ ---       │
        │ i64 ┆ str ┆ i64       │
        ╞═════╪═════╪═══════════╡
        │ 1   ┆ a   ┆ 2         │
        │ 2   ┆ b   ┆ 4         │
        │ 3   ┆ c   ┆ 6         │
        │ 1   ┆ c   ┆ 2         │
        └─────┴─────┴───────────┘

        Tip: it is better to implement this with an expression:

        >>> df.with_columns(
        ...     (pl.col("a") * 2).alias("a_times_2"),
        ... )  # doctest: +IGNORE_RESULT

        In a GroupBy context, each element of the column is itself a Series:

        >>> (
        ...     df.lazy().group_by("b").agg(pl.col("a")).collect()
        ... )  # doctest: +IGNORE_RESULT
        shape: (3, 2)
        ┌─────┬───────────┐
        │ b   ┆ a         │
        │ --- ┆ ---       │
        │ str ┆ list[i64] │
        ╞═════╪═══════════╡
        │ a   ┆ [1]       │
        │ b   ┆ [2]       │
        │ c   ┆ [3, 1]    │
        └─────┴───────────┘

        Therefore, from the user's point-of-view, the function is applied per-group:

        >>> (
        ...     df.lazy()
        ...     .group_by("b")
        ...     .agg(pl.col("a").map_elements(lambda x: x.sum()))
        ...     .collect()
        ... )  # doctest: +IGNORE_RESULT
        shape: (3, 2)
        ┌─────┬─────┐
        │ b   ┆ a   │
        │ --- ┆ --- │
        │ str ┆ i64 │
        ╞═════╪═════╡
        │ a   ┆ 1   │
        │ b   ┆ 2   │
        │ c   ┆ 4   │
        └─────┴─────┘

        Tip: again, it is better to implement this with an expression:

        >>> (
        ...     df.lazy()
        ...     .group_by("b", maintain_order=True)
        ...     .agg(pl.col("a").sum())
        ...     .collect()
        ... )  # doctest: +IGNORE_RESULT

        Window function application using `over` will behave as a GroupBy
        context, with your function receiving individual window groups:

        >>> df = pl.DataFrame(
        ...     {
        ...         "key": ["x", "x", "y", "x", "y", "z"],
        ...         "val": [1, 1, 1, 1, 1, 1],
        ...     }
        ... )
        >>> df.with_columns(
        ...     scaled=pl.col("val").map_elements(lambda s: s * len(s)).over("key"),
        ... ).sort("key")
        shape: (6, 3)
        ┌─────┬─────┬────────┐
        │ key ┆ val ┆ scaled │
        │ --- ┆ --- ┆ ---    │
        │ str ┆ i64 ┆ i64    │
        ╞═════╪═════╪════════╡
        │ x   ┆ 1   ┆ 3      │
        │ x   ┆ 1   ┆ 3      │
        │ x   ┆ 1   ┆ 3      │
        │ y   ┆ 1   ┆ 2      │
        │ y   ┆ 1   ┆ 2      │
        │ z   ┆ 1   ┆ 1      │
        └─────┴─────┴────────┘

        Note that this function would *also* be better-implemented natively:

        >>> df.with_columns(
        ...     scaled=(pl.col("val") * pl.col("val").count()).over("key"),
        ... ).sort(
        ...     "key"
        ... )  # doctest: +IGNORE_RESULT

        """
        # input x: Series of type list containing the group values
        from polars.utils.udfs import warn_on_inefficient_map

        root_names = self.meta.root_names()
        if len(root_names) > 0:
            warn_on_inefficient_map(function, columns=root_names, map_target="expr")

        if pass_name:

            def wrap_f(x: Series) -> Series:  # pragma: no cover
                def inner(s: Series) -> Series:  # pragma: no cover
                    return function(s.alias(x.name))

                with warnings.catch_warnings():
                    warnings.simplefilter("ignore", PolarsInefficientMapWarning)
                    return x.map_elements(
                        inner, return_dtype=return_dtype, skip_nulls=skip_nulls
                    )

        else:

            def wrap_f(x: Series) -> Series:  # pragma: no cover
                with warnings.catch_warnings():
                    warnings.simplefilter("ignore", PolarsInefficientMapWarning)
                    return x.map_elements(
                        function, return_dtype=return_dtype, skip_nulls=skip_nulls
                    )

        if strategy == "thread_local":
            return self.map_batches(wrap_f, agg_list=True, return_dtype=return_dtype)
        elif strategy == "threading":

            def wrap_threading(x: Series) -> Series:
                def get_lazy_promise(df: DataFrame) -> LazyFrame:
                    return df.lazy().select(
                        F.col("x").map_batches(
                            wrap_f, agg_list=True, return_dtype=return_dtype
                        )
                    )

                df = x.to_frame("x")

                if x.len() == 0:
                    return get_lazy_promise(df).collect().to_series()

                n_threads = threadpool_size()
                chunk_size = x.len() // n_threads
                remainder = x.len() % n_threads
                if chunk_size == 0:
                    chunk_sizes = [1 for _ in range(remainder)]
                else:
                    chunk_sizes = [
                        chunk_size + 1 if i < remainder else chunk_size
                        for i in range(n_threads)
                    ]

                # create partitions with LazyFrames
                # these are promises on a computation
                partitions = []
                b = 0
                for step in chunk_sizes:
                    a = b
                    b = b + step
                    partition_df = df[a:b]
                    partitions.append(get_lazy_promise(partition_df))

                out = [df.to_series() for df in F.collect_all(partitions)]
                return F.concat(out, rechunk=False)

            return self.map_batches(
                wrap_threading, agg_list=True, return_dtype=return_dtype
            )
        else:
            ValueError(f"Strategy {strategy} is not supported.")

    def flatten(self) -> Self:
        """
        Flatten a list or string column.

        Alias for :func:`polars.expr.list.ExprListNameSpace.explode`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group": ["a", "b", "b"],
        ...         "values": [[1, 2], [2, 3], [4]],
        ...     }
        ... )
        >>> df.group_by("group").agg(pl.col("values").flatten())  # doctest: +SKIP
        shape: (2, 2)
        ┌───────┬───────────┐
        │ group ┆ values    │
        │ ---   ┆ ---       │
        │ str   ┆ list[i64] │
        ╞═══════╪═══════════╡
        │ a     ┆ [1, 2]    │
        │ b     ┆ [2, 3, 4] │
        └───────┴───────────┘

        """
        return self._from_pyexpr(self._pyexpr.explode())

    def explode(self) -> Self:
        """
        Explode a list expression.

        This means that every item is expanded to a new row.

        Returns
        -------
        Expr
            Expression with the data type of the list elements.

        See Also
        --------
        Expr.list.explode : Explode a list column.
        Expr.str.explode : Explode a string column.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "group": ["a", "b"],
        ...         "values": [
        ...             [1, 2],
        ...             [3, 4],
        ...         ],
        ...     }
        ... )
        >>> df.select(pl.col("values").explode())
        shape: (4, 1)
        ┌────────┐
        │ values │
        │ ---    │
        │ i64    │
        ╞════════╡
        │ 1      │
        │ 2      │
        │ 3      │
        │ 4      │
        └────────┘

        """
        return self._from_pyexpr(self._pyexpr.explode())

    def implode(self) -> Self:
        """
        Aggregate values into a list.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": [4, 5, 6],
        ...     }
        ... )
        >>> df.select(pl.all().implode())
        shape: (1, 2)
        ┌───────────┬───────────┐
        │ a         ┆ b         │
        │ ---       ┆ ---       │
        │ list[i64] ┆ list[i64] │
        ╞═══════════╪═══════════╡
        │ [1, 2, 3] ┆ [4, 5, 6] │
        └───────────┴───────────┘

        """
        return self._from_pyexpr(self._pyexpr.implode())

    def gather_every(self, n: int) -> Self:
        """
        Take every nth value in the Series and return as a new Series.

        Parameters
        ----------
        n
            Gather every *n*-th row.

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 2, 3, 4, 5, 6, 7, 8, 9]})
        >>> df.select(pl.col("foo").gather_every(3))
        shape: (3, 1)
        ┌─────┐
        │ foo │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        │ 4   │
        │ 7   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.gather_every(n))

    def head(self, n: int | Expr = 10) -> Self:
        """
        Get the first `n` rows.

        Parameters
        ----------
        n
            Number of rows to return.

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 2, 3, 4, 5, 6, 7]})
        >>> df.head(3)
        shape: (3, 1)
        ┌─────┐
        │ foo │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        │ 2   │
        │ 3   │
        └─────┘

        """
        return self.slice(0, n)

    def tail(self, n: int | Expr = 10) -> Self:
        """
        Get the last `n` rows.

        Parameters
        ----------
        n
            Number of rows to return.

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 2, 3, 4, 5, 6, 7]})
        >>> df.tail(3)
        shape: (3, 1)
        ┌─────┐
        │ foo │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 5   │
        │ 6   │
        │ 7   │
        └─────┘

        """
        offset = -self._from_pyexpr(parse_as_expression(n))
        return self.slice(offset, n)

    def limit(self, n: int | Expr = 10) -> Self:
        """
        Get the first `n` rows (alias for :func:`Expr.head`).

        Parameters
        ----------
        n
            Number of rows to return.

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 2, 3, 4, 5, 6, 7]})
        >>> df.limit(3)
        shape: (3, 1)
        ┌─────┐
        │ foo │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        │ 2   │
        │ 3   │
        └─────┘

        """
        return self.head(n)

    def and_(self, *others: Any) -> Self:
        """
        Method equivalent of bitwise "and" operator `expr & other & ...`.

        Parameters
        ----------
        *others
            One or more integer or boolean expressions to evaluate/combine.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [5, 6, 7, 4, 8],
        ...         "y": [1.5, 2.5, 1.0, 4.0, -5.75],
        ...         "z": [-9, 2, -1, 4, 8],
        ...     }
        ... )
        >>> df.select(
        ...     (pl.col("x") >= pl.col("z"))
        ...     .and_(
        ...         pl.col("y") >= pl.col("z"),
        ...         pl.col("y") == pl.col("y"),
        ...         pl.col("z") <= pl.col("x"),
        ...         pl.col("y") != pl.col("x"),
        ...     )
        ...     .alias("all")
        ... )
        shape: (5, 1)
        ┌───────┐
        │ all   │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ true  │
        │ true  │
        │ true  │
        │ false │
        │ false │
        └───────┘

        """
        return reduce(operator.and_, (self,) + others)

    def or_(self, *others: Any) -> Self:
        """
        Method equivalent of bitwise "or" operator `expr | other | ...`.

        Parameters
        ----------
        *others
            One or more integer or boolean expressions to evaluate/combine.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [5, 6, 7, 4, 8],
        ...         "y": [1.5, 2.5, 1.0, 4.0, -5.75],
        ...         "z": [-9, 2, -1, 4, 8],
        ...     }
        ... )
        >>> df.select(
        ...     (pl.col("x") == pl.col("y"))
        ...     .or_(
        ...         pl.col("x") == pl.col("y"),
        ...         pl.col("y") == pl.col("z"),
        ...         pl.col("y").cast(int) == pl.col("z"),
        ...     )
        ...     .alias("any")
        ... )
        shape: (5, 1)
        ┌───────┐
        │ any   │
        │ ---   │
        │ bool  │
        ╞═══════╡
        │ false │
        │ true  │
        │ false │
        │ true  │
        │ false │
        └───────┘

        """
        return reduce(operator.or_, (self,) + others)

    def eq(self, other: Any) -> Self:
        """
        Method equivalent of equality operator `expr == other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [1.0, 2.0, float("nan"), 4.0],
        ...         "y": [2.0, 2.0, float("nan"), 4.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").eq(pl.col("y")).alias("x == y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬────────┐
        │ x   ┆ y   ┆ x == y │
        │ --- ┆ --- ┆ ---    │
        │ f64 ┆ f64 ┆ bool   │
        ╞═════╪═════╪════════╡
        │ 1.0 ┆ 2.0 ┆ false  │
        │ 2.0 ┆ 2.0 ┆ true   │
        │ NaN ┆ NaN ┆ false  │
        │ 4.0 ┆ 4.0 ┆ true   │
        └─────┴─────┴────────┘

        """
        return self.__eq__(other)

    def eq_missing(self, other: Any) -> Self:
        """
        Method equivalent of equality operator `expr == other` where `None == None`.

        This differs from default `eq` where null values are propagated.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [1.0, 2.0, float("nan"), 4.0, None, None],
        ...         "y": [2.0, 2.0, float("nan"), 4.0, 5.0, None],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").eq(pl.col("y")).alias("x eq y"),
        ...     pl.col("x").eq_missing(pl.col("y")).alias("x eq_missing y"),
        ... )
        shape: (6, 4)
        ┌──────┬──────┬────────┬────────────────┐
        │ x    ┆ y    ┆ x eq y ┆ x eq_missing y │
        │ ---  ┆ ---  ┆ ---    ┆ ---            │
        │ f64  ┆ f64  ┆ bool   ┆ bool           │
        ╞══════╪══════╪════════╪════════════════╡
        │ 1.0  ┆ 2.0  ┆ false  ┆ false          │
        │ 2.0  ┆ 2.0  ┆ true   ┆ true           │
        │ NaN  ┆ NaN  ┆ false  ┆ false          │
        │ 4.0  ┆ 4.0  ┆ true   ┆ true           │
        │ null ┆ 5.0  ┆ null   ┆ false          │
        │ null ┆ null ┆ null   ┆ true           │
        └──────┴──────┴────────┴────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.eq_missing(self._to_pyexpr(other)))

    def ge(self, other: Any) -> Self:
        """
        Method equivalent of "greater than or equal" operator `expr >= other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [5.0, 4.0, float("nan"), 2.0],
        ...         "y": [5.0, 3.0, float("nan"), 1.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").ge(pl.col("y")).alias("x >= y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬────────┐
        │ x   ┆ y   ┆ x >= y │
        │ --- ┆ --- ┆ ---    │
        │ f64 ┆ f64 ┆ bool   │
        ╞═════╪═════╪════════╡
        │ 5.0 ┆ 5.0 ┆ true   │
        │ 4.0 ┆ 3.0 ┆ true   │
        │ NaN ┆ NaN ┆ false  │
        │ 2.0 ┆ 1.0 ┆ true   │
        └─────┴─────┴────────┘

        """
        return self.__ge__(other)

    def gt(self, other: Any) -> Self:
        """
        Method equivalent of "greater than" operator `expr > other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [5.0, 4.0, float("nan"), 2.0],
        ...         "y": [5.0, 3.0, float("nan"), 1.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").gt(pl.col("y")).alias("x > y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬───────┐
        │ x   ┆ y   ┆ x > y │
        │ --- ┆ --- ┆ ---   │
        │ f64 ┆ f64 ┆ bool  │
        ╞═════╪═════╪═══════╡
        │ 5.0 ┆ 5.0 ┆ false │
        │ 4.0 ┆ 3.0 ┆ true  │
        │ NaN ┆ NaN ┆ false │
        │ 2.0 ┆ 1.0 ┆ true  │
        └─────┴─────┴───────┘

        """
        return self.__gt__(other)

    def le(self, other: Any) -> Self:
        """
        Method equivalent of "less than or equal" operator `expr <= other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [5.0, 4.0, float("nan"), 0.5],
        ...         "y": [5.0, 3.5, float("nan"), 2.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").le(pl.col("y")).alias("x <= y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬────────┐
        │ x   ┆ y   ┆ x <= y │
        │ --- ┆ --- ┆ ---    │
        │ f64 ┆ f64 ┆ bool   │
        ╞═════╪═════╪════════╡
        │ 5.0 ┆ 5.0 ┆ true   │
        │ 4.0 ┆ 3.5 ┆ false  │
        │ NaN ┆ NaN ┆ false  │
        │ 0.5 ┆ 2.0 ┆ true   │
        └─────┴─────┴────────┘

        """
        return self.__le__(other)

    def lt(self, other: Any) -> Self:
        """
        Method equivalent of "less than" operator `expr < other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [1.0, 2.0, float("nan"), 3.0],
        ...         "y": [2.0, 2.0, float("nan"), 4.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").lt(pl.col("y")).alias("x < y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬───────┐
        │ x   ┆ y   ┆ x < y │
        │ --- ┆ --- ┆ ---   │
        │ f64 ┆ f64 ┆ bool  │
        ╞═════╪═════╪═══════╡
        │ 1.0 ┆ 2.0 ┆ true  │
        │ 2.0 ┆ 2.0 ┆ false │
        │ NaN ┆ NaN ┆ false │
        │ 3.0 ┆ 4.0 ┆ true  │
        └─────┴─────┴───────┘

        """
        return self.__lt__(other)

    def ne(self, other: Any) -> Self:
        """
        Method equivalent of inequality operator `expr != other`.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [1.0, 2.0, float("nan"), 4.0],
        ...         "y": [2.0, 2.0, float("nan"), 4.0],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").ne(pl.col("y")).alias("x != y"),
        ... )
        shape: (4, 3)
        ┌─────┬─────┬────────┐
        │ x   ┆ y   ┆ x != y │
        │ --- ┆ --- ┆ ---    │
        │ f64 ┆ f64 ┆ bool   │
        ╞═════╪═════╪════════╡
        │ 1.0 ┆ 2.0 ┆ true   │
        │ 2.0 ┆ 2.0 ┆ false  │
        │ NaN ┆ NaN ┆ true   │
        │ 4.0 ┆ 4.0 ┆ false  │
        └─────┴─────┴────────┘

        """
        return self.__ne__(other)

    def ne_missing(self, other: Any) -> Self:
        """
        Method equivalent of equality operator `expr != other` where `None == None`.

        This differs from default `ne` where null values are propagated.

        Parameters
        ----------
        other
            A literal or expression value to compare with.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={
        ...         "x": [1.0, 2.0, float("nan"), 4.0, None, None],
        ...         "y": [2.0, 2.0, float("nan"), 4.0, 5.0, None],
        ...     }
        ... )
        >>> df.with_columns(
        ...     pl.col("x").ne(pl.col("y")).alias("x ne y"),
        ...     pl.col("x").ne_missing(pl.col("y")).alias("x ne_missing y"),
        ... )
        shape: (6, 4)
        ┌──────┬──────┬────────┬────────────────┐
        │ x    ┆ y    ┆ x ne y ┆ x ne_missing y │
        │ ---  ┆ ---  ┆ ---    ┆ ---            │
        │ f64  ┆ f64  ┆ bool   ┆ bool           │
        ╞══════╪══════╪════════╪════════════════╡
        │ 1.0  ┆ 2.0  ┆ true   ┆ true           │
        │ 2.0  ┆ 2.0  ┆ false  ┆ false          │
        │ NaN  ┆ NaN  ┆ true   ┆ true           │
        │ 4.0  ┆ 4.0  ┆ false  ┆ false          │
        │ null ┆ 5.0  ┆ null   ┆ true           │
        │ null ┆ null ┆ null   ┆ false          │
        └──────┴──────┴────────┴────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.neq_missing(self._to_pyexpr(other)))

    def add(self, other: Any) -> Self:
        """
        Method equivalent of addition operator `expr + other`.

        Parameters
        ----------
        other
            numeric or string value; accepts expression input.

        Examples
        --------
        >>> df = pl.DataFrame({"x": [1, 2, 3, 4, 5]})
        >>> df.with_columns(
        ...     pl.col("x").add(2).alias("x+int"),
        ...     pl.col("x").add(pl.col("x").cum_prod()).alias("x+expr"),
        ... )
        shape: (5, 3)
        ┌─────┬───────┬────────┐
        │ x   ┆ x+int ┆ x+expr │
        │ --- ┆ ---   ┆ ---    │
        │ i64 ┆ i64   ┆ i64    │
        ╞═════╪═══════╪════════╡
        │ 1   ┆ 3     ┆ 2      │
        │ 2   ┆ 4     ┆ 4      │
        │ 3   ┆ 5     ┆ 9      │
        │ 4   ┆ 6     ┆ 28     │
        │ 5   ┆ 7     ┆ 125    │
        └─────┴───────┴────────┘

        >>> df = pl.DataFrame(
        ...     {"x": ["a", "d", "g"], "y": ["b", "e", "h"], "z": ["c", "f", "i"]}
        ... )
        >>> df.with_columns(pl.col("x").add(pl.col("y")).add(pl.col("z")).alias("xyz"))
        shape: (3, 4)
        ┌─────┬─────┬─────┬─────┐
        │ x   ┆ y   ┆ z   ┆ xyz │
        │ --- ┆ --- ┆ --- ┆ --- │
        │ str ┆ str ┆ str ┆ str │
        ╞═════╪═════╪═════╪═════╡
        │ a   ┆ b   ┆ c   ┆ abc │
        │ d   ┆ e   ┆ f   ┆ def │
        │ g   ┆ h   ┆ i   ┆ ghi │
        └─────┴─────┴─────┴─────┘

        """
        return self.__add__(other)

    def floordiv(self, other: Any) -> Self:
        """
        Method equivalent of integer division operator `expr // other`.

        Parameters
        ----------
        other
            Numeric literal or expression value.

        See Also
        --------
        truediv

        Examples
        --------
        >>> df = pl.DataFrame({"x": [1, 2, 3, 4, 5]})
        >>> df.with_columns(
        ...     pl.col("x").truediv(2).alias("x/2"),
        ...     pl.col("x").floordiv(2).alias("x//2"),
        ... )
        shape: (5, 3)
        ┌─────┬─────┬──────┐
        │ x   ┆ x/2 ┆ x//2 │
        │ --- ┆ --- ┆ ---  │
        │ i64 ┆ f64 ┆ i64  │
        ╞═════╪═════╪══════╡
        │ 1   ┆ 0.5 ┆ 0    │
        │ 2   ┆ 1.0 ┆ 1    │
        │ 3   ┆ 1.5 ┆ 1    │
        │ 4   ┆ 2.0 ┆ 2    │
        │ 5   ┆ 2.5 ┆ 2    │
        └─────┴─────┴──────┘

        """
        return self.__floordiv__(other)

    def mod(self, other: Any) -> Self:
        """
        Method equivalent of modulus operator `expr % other`.

        Parameters
        ----------
        other
            Numeric literal or expression value.

        Examples
        --------
        >>> df = pl.DataFrame({"x": [0, 1, 2, 3, 4]})
        >>> df.with_columns(pl.col("x").mod(2).alias("x%2"))
        shape: (5, 2)
        ┌─────┬─────┐
        │ x   ┆ x%2 │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 0   ┆ 0   │
        │ 1   ┆ 1   │
        │ 2   ┆ 0   │
        │ 3   ┆ 1   │
        │ 4   ┆ 0   │
        └─────┴─────┘

        """
        return self.__mod__(other)

    def mul(self, other: Any) -> Self:
        """
        Method equivalent of multiplication operator `expr * other`.

        Parameters
        ----------
        other
            Numeric literal or expression value.

        Examples
        --------
        >>> df = pl.DataFrame({"x": [1, 2, 4, 8, 16]})
        >>> df.with_columns(
        ...     pl.col("x").mul(2).alias("x*2"),
        ...     pl.col("x").mul(pl.col("x").log(2)).alias("x * xlog2"),
        ... )
        shape: (5, 3)
        ┌─────┬─────┬───────────┐
        │ x   ┆ x*2 ┆ x * xlog2 │
        │ --- ┆ --- ┆ ---       │
        │ i64 ┆ i64 ┆ f64       │
        ╞═════╪═════╪═══════════╡
        │ 1   ┆ 2   ┆ 0.0       │
        │ 2   ┆ 4   ┆ 2.0       │
        │ 4   ┆ 8   ┆ 8.0       │
        │ 8   ┆ 16  ┆ 24.0      │
        │ 16  ┆ 32  ┆ 64.0      │
        └─────┴─────┴───────────┘

        """
        return self.__mul__(other)

    def sub(self, other: Any) -> Self:
        """
        Method equivalent of subtraction operator `expr - other`.

        Parameters
        ----------
        other
            Numeric literal or expression value.

        Examples
        --------
        >>> df = pl.DataFrame({"x": [0, 1, 2, 3, 4]})
        >>> df.with_columns(
        ...     pl.col("x").sub(2).alias("x-2"),
        ...     pl.col("x").sub(pl.col("x").cum_sum()).alias("x-expr"),
        ... )
        shape: (5, 3)
        ┌─────┬─────┬────────┐
        │ x   ┆ x-2 ┆ x-expr │
        │ --- ┆ --- ┆ ---    │
        │ i64 ┆ i64 ┆ i64    │
        ╞═════╪═════╪════════╡
        │ 0   ┆ -2  ┆ 0      │
        │ 1   ┆ -1  ┆ 0      │
        │ 2   ┆ 0   ┆ -1     │
        │ 3   ┆ 1   ┆ -3     │
        │ 4   ┆ 2   ┆ -6     │
        └─────┴─────┴────────┘

        """
        return self.__sub__(other)

    def truediv(self, other: Any) -> Self:
        """
        Method equivalent of float division operator `expr / other`.

        Parameters
        ----------
        other
            Numeric literal or expression value.

        Notes
        -----
        Zero-division behaviour follows IEEE-754:

        0/0: Invalid operation - mathematically undefined, returns NaN.
        n/0: On finite operands gives an exact infinite result, eg: ±infinity.

        See Also
        --------
        floordiv

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     data={"x": [-2, -1, 0, 1, 2], "y": [0.5, 0.0, 0.0, -4.0, -0.5]}
        ... )
        >>> df.with_columns(
        ...     pl.col("x").truediv(2).alias("x/2"),
        ...     pl.col("x").truediv(pl.col("y")).alias("x/y"),
        ... )
        shape: (5, 4)
        ┌─────┬──────┬──────┬───────┐
        │ x   ┆ y    ┆ x/2  ┆ x/y   │
        │ --- ┆ ---  ┆ ---  ┆ ---   │
        │ i64 ┆ f64  ┆ f64  ┆ f64   │
        ╞═════╪══════╪══════╪═══════╡
        │ -2  ┆ 0.5  ┆ -1.0 ┆ -4.0  │
        │ -1  ┆ 0.0  ┆ -0.5 ┆ -inf  │
        │ 0   ┆ 0.0  ┆ 0.0  ┆ NaN   │
        │ 1   ┆ -4.0 ┆ 0.5  ┆ -0.25 │
        │ 2   ┆ -0.5 ┆ 1.0  ┆ -4.0  │
        └─────┴──────┴──────┴───────┘

        """
        return self.__truediv__(other)

    def pow(self, exponent: int | float | None | Series | Expr) -> Self:
        """
        Method equivalent of exponentiation operator `expr ** exponent`.

        Parameters
        ----------
        exponent
            Numeric literal or expression exponent value.

        Examples
        --------
        >>> df = pl.DataFrame({"x": [1, 2, 4, 8]})
        >>> df.with_columns(
        ...     pl.col("x").pow(3).alias("cube"),
        ...     pl.col("x").pow(pl.col("x").log(2)).alias("x ** xlog2"),
        ... )
        shape: (4, 3)
        ┌─────┬───────┬────────────┐
        │ x   ┆ cube  ┆ x ** xlog2 │
        │ --- ┆ ---   ┆ ---        │
        │ i64 ┆ f64   ┆ f64        │
        ╞═════╪═══════╪════════════╡
        │ 1   ┆ 1.0   ┆ 1.0        │
        │ 2   ┆ 8.0   ┆ 2.0        │
        │ 4   ┆ 64.0  ┆ 16.0       │
        │ 8   ┆ 512.0 ┆ 512.0      │
        └─────┴───────┴────────────┘

        """
        exponent = parse_as_expression(exponent)
        return self._from_pyexpr(self._pyexpr.pow(exponent))

    def xor(self, other: Any) -> Self:
        """
        Method equivalent of bitwise exclusive-or operator `expr ^ other`.

        Parameters
        ----------
        other
            Integer or boolean value; accepts expression input.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {"x": [True, False, True, False], "y": [True, True, False, False]}
        ... )
        >>> df.with_columns(pl.col("x").xor(pl.col("y")).alias("x ^ y"))
        shape: (4, 3)
        ┌───────┬───────┬───────┐
        │ x     ┆ y     ┆ x ^ y │
        │ ---   ┆ ---   ┆ ---   │
        │ bool  ┆ bool  ┆ bool  │
        ╞═══════╪═══════╪═══════╡
        │ true  ┆ true  ┆ false │
        │ false ┆ true  ┆ true  │
        │ true  ┆ false ┆ true  │
        │ false ┆ false ┆ false │
        └───────┴───────┴───────┘

        >>> def binary_string(n: int) -> str:
        ...     return bin(n)[2:].zfill(8)
        >>>
        >>> df = pl.DataFrame(
        ...     data={"x": [10, 8, 250, 66], "y": [1, 2, 3, 4]},
        ...     schema={"x": pl.UInt8, "y": pl.UInt8},
        ... )
        >>> df.with_columns(
        ...     pl.col("x").map_elements(binary_string).alias("bin_x"),
        ...     pl.col("y").map_elements(binary_string).alias("bin_y"),
        ...     pl.col("x").xor(pl.col("y")).alias("xor_xy"),
        ...     pl.col("x")
        ...     .xor(pl.col("y"))
        ...     .map_elements(binary_string)
        ...     .alias("bin_xor_xy"),
        ... )
        shape: (4, 6)
        ┌─────┬─────┬──────────┬──────────┬────────┬────────────┐
        │ x   ┆ y   ┆ bin_x    ┆ bin_y    ┆ xor_xy ┆ bin_xor_xy │
        │ --- ┆ --- ┆ ---      ┆ ---      ┆ ---    ┆ ---        │
        │ u8  ┆ u8  ┆ str      ┆ str      ┆ u8     ┆ str        │
        ╞═════╪═════╪══════════╪══════════╪════════╪════════════╡
        │ 10  ┆ 1   ┆ 00001010 ┆ 00000001 ┆ 11     ┆ 00001011   │
        │ 8   ┆ 2   ┆ 00001000 ┆ 00000010 ┆ 10     ┆ 00001010   │
        │ 250 ┆ 3   ┆ 11111010 ┆ 00000011 ┆ 249    ┆ 11111001   │
        │ 66  ┆ 4   ┆ 01000010 ┆ 00000100 ┆ 70     ┆ 01000110   │
        └─────┴─────┴──────────┴──────────┴────────┴────────────┘

        """
        return self.__xor__(other)

    def is_in(self, other: Expr | Collection[Any] | Series) -> Self:
        """
        Check if elements of this expression are present in the other Series.

        Parameters
        ----------
        other
            Series or sequence of primitive type.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {"sets": [[1, 2, 3], [1, 2], [9, 10]], "optional_members": [1, 2, 3]}
        ... )
        >>> df.with_columns(contains=pl.col("optional_members").is_in("sets"))
        shape: (3, 3)
        ┌───────────┬──────────────────┬──────────┐
        │ sets      ┆ optional_members ┆ contains │
        │ ---       ┆ ---              ┆ ---      │
        │ list[i64] ┆ i64              ┆ bool     │
        ╞═══════════╪══════════════════╪══════════╡
        │ [1, 2, 3] ┆ 1                ┆ true     │
        │ [1, 2]    ┆ 2                ┆ true     │
        │ [9, 10]   ┆ 3                ┆ false    │
        └───────────┴──────────────────┴──────────┘

        """
        if isinstance(other, Collection) and not isinstance(other, str):
            if isinstance(other, (Set, FrozenSet)):
                other = list(other)
            implied_dtype = Null if len(other) == 0 else None
            other = F.lit(pl.Series(other, dtype=implied_dtype))._pyexpr
        else:
            other = parse_as_expression(other)
        return self._from_pyexpr(self._pyexpr.is_in(other))

    def repeat_by(self, by: pl.Series | Expr | str | int) -> Self:
        """
        Repeat the elements in this Series as specified in the given expression.

        The repeated elements are expanded into a `List`.

        Parameters
        ----------
        by
            Numeric column that determines how often the values will be repeated.
            The column will be coerced to UInt32. Give this dtype to make the coercion a
            no-op.

        Returns
        -------
        Expr
            Expression of data type :class:`List`, where the inner data type is equal
            to the original data type.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": ["x", "y", "z"],
        ...         "n": [1, 2, 3],
        ...     }
        ... )
        >>> df.select(pl.col("a").repeat_by("n"))
        shape: (3, 1)
        ┌─────────────────┐
        │ a               │
        │ ---             │
        │ list[str]       │
        ╞═════════════════╡
        │ ["x"]           │
        │ ["y", "y"]      │
        │ ["z", "z", "z"] │
        └─────────────────┘

        """
        by = parse_as_expression(by)
        return self._from_pyexpr(self._pyexpr.repeat_by(by))

    def is_between(
        self,
        lower_bound: IntoExpr,
        upper_bound: IntoExpr,
        closed: ClosedInterval = "both",
    ) -> Self:
        """
        Check if this expression is between the given start and end values.

        Parameters
        ----------
        lower_bound
            Lower bound value. Accepts expression input. Strings are parsed as column
            names, other non-expression inputs are parsed as literals.
        upper_bound
            Upper bound value. Accepts expression input. Strings are parsed as column
            names, other non-expression inputs are parsed as literals.
        closed : {'both', 'left', 'right', 'none'}
            Define which sides of the interval are closed (inclusive).

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        Examples
        --------
        >>> df = pl.DataFrame({"num": [1, 2, 3, 4, 5]})
        >>> df.with_columns(pl.col("num").is_between(2, 4).alias("is_between"))
        shape: (5, 2)
        ┌─────┬────────────┐
        │ num ┆ is_between │
        │ --- ┆ ---        │
        │ i64 ┆ bool       │
        ╞═════╪════════════╡
        │ 1   ┆ false      │
        │ 2   ┆ true       │
        │ 3   ┆ true       │
        │ 4   ┆ true       │
        │ 5   ┆ false      │
        └─────┴────────────┘

        Use the `closed` argument to include or exclude the values at the bounds:

        >>> df.with_columns(
        ...     pl.col("num").is_between(2, 4, closed="left").alias("is_between")
        ... )
        shape: (5, 2)
        ┌─────┬────────────┐
        │ num ┆ is_between │
        │ --- ┆ ---        │
        │ i64 ┆ bool       │
        ╞═════╪════════════╡
        │ 1   ┆ false      │
        │ 2   ┆ true       │
        │ 3   ┆ true       │
        │ 4   ┆ false      │
        │ 5   ┆ false      │
        └─────┴────────────┘

        You can also use strings as well as numeric/temporal values (note: ensure that
        string literals are wrapped with `lit` so as not to conflate them with
        column names):

        >>> df = pl.DataFrame({"a": ["a", "b", "c", "d", "e"]})
        >>> df.with_columns(
        ...     pl.col("a")
        ...     .is_between(pl.lit("a"), pl.lit("c"), closed="both")
        ...     .alias("is_between")
        ... )
        shape: (5, 2)
        ┌─────┬────────────┐
        │ a   ┆ is_between │
        │ --- ┆ ---        │
        │ str ┆ bool       │
        ╞═════╪════════════╡
        │ a   ┆ true       │
        │ b   ┆ true       │
        │ c   ┆ true       │
        │ d   ┆ false      │
        │ e   ┆ false      │
        └─────┴────────────┘

        """
        lower_bound = self._from_pyexpr(parse_as_expression(lower_bound))
        upper_bound = self._from_pyexpr(parse_as_expression(upper_bound))

        if closed == "none":
            return (self > lower_bound) & (self < upper_bound)
        elif closed == "both":
            return (self >= lower_bound) & (self <= upper_bound)
        elif closed == "right":
            return (self > lower_bound) & (self <= upper_bound)
        elif closed == "left":
            return (self >= lower_bound) & (self < upper_bound)
        else:
            raise ValueError(
                "`closed` must be one of {'left', 'right', 'both', 'none'},"
                f" got {closed!r}"
            )

    def hash(
        self,
        seed: int = 0,
        seed_1: int | None = None,
        seed_2: int | None = None,
        seed_3: int | None = None,
    ) -> Self:
        """
        Hash the elements in the selection.

        The hash value is of type `UInt64`.

        Parameters
        ----------
        seed
            Random seed parameter. Defaults to 0.
        seed_1
            Random seed parameter. Defaults to `seed` if not set.
        seed_2
            Random seed parameter. Defaults to `seed` if not set.
        seed_3
            Random seed parameter. Defaults to `seed` if not set.

        Notes
        -----
        This implementation of :func:`rows` does not guarantee stable results
        across different Polars versions. Its stability is only guaranteed within a
        single version.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, 2, None],
        ...         "b": ["x", None, "z"],
        ...     }
        ... )
        >>> df.with_columns(pl.all().hash(10, 20, 30, 40))  # doctest: +IGNORE_RESULT
        shape: (3, 2)
        ┌──────────────────────┬──────────────────────┐
        │ a                    ┆ b                    │
        │ ---                  ┆ ---                  │
        │ u64                  ┆ u64                  │
        ╞══════════════════════╪══════════════════════╡
        │ 9774092659964970114  ┆ 13614470193936745724 │
        │ 1101441246220388612  ┆ 11638928888656214026 │
        │ 11638928888656214026 ┆ 13382926553367784577 │
        └──────────────────────┴──────────────────────┘

        """
        k0 = seed
        k1 = seed_1 if seed_1 is not None else seed
        k2 = seed_2 if seed_2 is not None else seed
        k3 = seed_3 if seed_3 is not None else seed
        return self._from_pyexpr(self._pyexpr.hash(k0, k1, k2, k3))

    def reinterpret(self, *, signed: bool = True) -> Self:
        """
        Reinterpret the underlying bits as a signed/unsigned integer.

        This operation is only allowed for 64bit integers. For lower bits integers,
        you can safely use that cast operation.

        Parameters
        ----------
        signed
            If True, reinterpret as `pl.Int64`. Otherwise, reinterpret as `pl.UInt64`.

        Examples
        --------
        >>> s = pl.Series("a", [1, 1, 2], dtype=pl.UInt64)
        >>> df = pl.DataFrame([s])
        >>> df.select(
        ...     [
        ...         pl.col("a").reinterpret(signed=True).alias("reinterpreted"),
        ...         pl.col("a").alias("original"),
        ...     ]
        ... )
        shape: (3, 2)
        ┌───────────────┬──────────┐
        │ reinterpreted ┆ original │
        │ ---           ┆ ---      │
        │ i64           ┆ u64      │
        ╞═══════════════╪══════════╡
        │ 1             ┆ 1        │
        │ 1             ┆ 1        │
        │ 2             ┆ 2        │
        └───────────────┴──────────┘

        """
        return self._from_pyexpr(self._pyexpr.reinterpret(signed))

    def inspect(self, fmt: str = "{}") -> Self:
        """
        Print the value that this expression evaluates to and pass on the value.

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 1, 2]})
        >>> df.select(pl.col("foo").cum_sum().inspect("value is: {}").alias("bar"))
        value is: shape: (3,)
        Series: 'foo' [i64]
        [
            1
            2
            4
        ]
        shape: (3, 1)
        ┌─────┐
        │ bar │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 1   │
        │ 2   │
        │ 4   │
        └─────┘

        """

        def inspect(s: Series) -> Series:  # pragma: no cover
            print(fmt.format(s))
            return s

        return self.map_batches(inspect, return_dtype=None, agg_list=True)

    def interpolate(self, method: InterpolationMethod = "linear") -> Self:
        """
        Fill null values using interpolation.

        Parameters
        ----------
        method : {'linear', 'nearest'}
            Interpolation method.

        Examples
        --------
        Fill null values using linear interpolation.

        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [1, None, 3],
        ...         "b": [1.0, float("nan"), 3.0],
        ...     }
        ... )
        >>> df.select(pl.all().interpolate())
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ f64 ┆ f64 │
        ╞═════╪═════╡
        │ 1.0 ┆ 1.0 │
        │ 2.0 ┆ NaN │
        │ 3.0 ┆ 3.0 │
        └─────┴─────┘

        Fill null values using nearest interpolation.

        >>> df.select(pl.all().interpolate("nearest"))
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ f64 │
        ╞═════╪═════╡
        │ 1   ┆ 1.0 │
        │ 3   ┆ NaN │
        │ 3   ┆ 3.0 │
        └─────┴─────┘

        Regrid data to a new grid.

        >>> df_original_grid = pl.DataFrame(
        ...     {
        ...         "grid_points": [1, 3, 10],
        ...         "values": [2.0, 6.0, 20.0],
        ...     }
        ... )  # Interpolate from this to the new grid
        >>> df_new_grid = pl.DataFrame({"grid_points": range(1, 11)})
        >>> df_new_grid.join(
        ...     df_original_grid, on="grid_points", how="left"
        ... ).with_columns(pl.col("values").interpolate())
        shape: (10, 2)
        ┌─────────────┬────────┐
        │ grid_points ┆ values │
        │ ---         ┆ ---    │
        │ i64         ┆ f64    │
        ╞═════════════╪════════╡
        │ 1           ┆ 2.0    │
        │ 2           ┆ 4.0    │
        │ 3           ┆ 6.0    │
        │ 4           ┆ 8.0    │
        │ …           ┆ …      │
        │ 7           ┆ 14.0   │
        │ 8           ┆ 16.0   │
        │ 9           ┆ 18.0   │
        │ 10          ┆ 20.0   │
        └─────────────┴────────┘

        """
        return self._from_pyexpr(self._pyexpr.interpolate(method))

    @warn_closed_future_change()
    def rolling_min(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Apply a rolling min (moving min) over the values in this array.

        A window of length `window_size` will traverse the array. The values that fill
        this window will (optionally) be multiplied with the weights given by the
        `weight` vector. The resulting values will be aggregated to their min.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic
            temporal size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_min=pl.col("A").rolling_min(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_min │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.0         │
        │ 3.0 ┆ 2.0         │
        │ 4.0 ┆ 3.0         │
        │ 5.0 ┆ 4.0         │
        │ 6.0 ┆ 5.0         │
        └─────┴─────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_min=pl.col("A").rolling_min(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_min │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 0.25        │
        │ 3.0 ┆ 0.5         │
        │ 4.0 ┆ 0.75        │
        │ 5.0 ┆ 1.0         │
        │ 6.0 ┆ 1.25        │
        └─────┴─────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_min=pl.col("A").rolling_min(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_min │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.0         │
        │ 3.0 ┆ 2.0         │
        │ 4.0 ┆ 3.0         │
        │ 5.0 ┆ 4.0         │
        │ 6.0 ┆ null        │
        └─────┴─────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘
        >>> df_temporal.with_columns(
        ...     rolling_row_min=pl.col("row_nr").rolling_min(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_min │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ u32             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null            │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0               │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 0               │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 1               │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 19              │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 20              │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 21              │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 22              │
        └────────┴─────────────────────┴─────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_min(
                window_size, weights, min_periods, center, by, closed, warn_if_unsorted
            )
        )

    @warn_closed_future_change()
    def rolling_max(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Apply a rolling max (moving max) over the values in this array.

        A window of length `window_size` will traverse the array. The values that fill
        this window will (optionally) be multiplied with the weights given by the
        `weight` vector. The resulting values will be aggregated to their max.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal, for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_max=pl.col("A").rolling_max(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_max │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 2.0         │
        │ 3.0 ┆ 3.0         │
        │ 4.0 ┆ 4.0         │
        │ 5.0 ┆ 5.0         │
        │ 6.0 ┆ 6.0         │
        └─────┴─────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_max=pl.col("A").rolling_max(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_max │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.5         │
        │ 3.0 ┆ 2.25        │
        │ 4.0 ┆ 3.0         │
        │ 5.0 ┆ 3.75        │
        │ 6.0 ┆ 4.5         │
        └─────┴─────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_max=pl.col("A").rolling_max(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_max │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 3.0         │
        │ 3.0 ┆ 4.0         │
        │ 4.0 ┆ 5.0         │
        │ 5.0 ┆ 6.0         │
        │ 6.0 ┆ null        │
        └─────┴─────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘

        Compute the rolling max with the default left closure of temporal windows

        >>> df_temporal.with_columns(
        ...     rolling_row_max=pl.col("row_nr").rolling_max(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_max │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ u32             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null            │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0               │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 1               │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 2               │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 20              │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 21              │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 22              │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 23              │
        └────────┴─────────────────────┴─────────────────┘

        Compute the rolling max with the closure of windows on both sides

        >>> df_temporal.with_columns(
        ...     rolling_row_max=pl.col("row_nr").rolling_max(
        ...         window_size="2h", by="date", closed="both"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_max │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ u32             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ 0               │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 1               │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 2               │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 3               │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 21              │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 22              │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 23              │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 24              │
        └────────┴─────────────────────┴─────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_max(
                window_size, weights, min_periods, center, by, closed, warn_if_unsorted
            )
        )

    @warn_closed_future_change()
    def rolling_mean(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Apply a rolling mean (moving mean) over the values in this array.

        A window of length `window_size` will traverse the array. The values that fill
        this window will (optionally) be multiplied with the weights given by the
        `weight` vector. The resulting values will be aggregated to their mean.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_mean=pl.col("A").rolling_mean(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────┐
        │ A   ┆ rolling_mean │
        │ --- ┆ ---          │
        │ f64 ┆ f64          │
        ╞═════╪══════════════╡
        │ 1.0 ┆ null         │
        │ 2.0 ┆ 1.5          │
        │ 3.0 ┆ 2.5          │
        │ 4.0 ┆ 3.5          │
        │ 5.0 ┆ 4.5          │
        │ 6.0 ┆ 5.5          │
        └─────┴──────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_mean=pl.col("A").rolling_mean(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────┐
        │ A   ┆ rolling_mean │
        │ --- ┆ ---          │
        │ f64 ┆ f64          │
        ╞═════╪══════════════╡
        │ 1.0 ┆ null         │
        │ 2.0 ┆ 1.75         │
        │ 3.0 ┆ 2.75         │
        │ 4.0 ┆ 3.75         │
        │ 5.0 ┆ 4.75         │
        │ 6.0 ┆ 5.75         │
        └─────┴──────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_mean=pl.col("A").rolling_mean(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────┐
        │ A   ┆ rolling_mean │
        │ --- ┆ ---          │
        │ f64 ┆ f64          │
        ╞═════╪══════════════╡
        │ 1.0 ┆ null         │
        │ 2.0 ┆ 2.0          │
        │ 3.0 ┆ 3.0          │
        │ 4.0 ┆ 4.0          │
        │ 5.0 ┆ 5.0          │
        │ 6.0 ┆ null         │
        └─────┴──────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘

        Compute the rolling mean with the default left closure of temporal windows

        >>> df_temporal.with_columns(
        ...     rolling_row_mean=pl.col("row_nr").rolling_mean(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬──────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_mean │
        │ ---    ┆ ---                 ┆ ---              │
        │ u32    ┆ datetime[μs]        ┆ f64              │
        ╞════════╪═════════════════════╪══════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null             │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.0              │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 0.5              │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 1.5              │
        │ …      ┆ …                   ┆ …                │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 19.5             │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 20.5             │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 21.5             │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 22.5             │
        └────────┴─────────────────────┴──────────────────┘

        Compute the rolling mean with the closure of windows on both sides

        >>> df_temporal.with_columns(
        ...     rolling_row_mean=pl.col("row_nr").rolling_mean(
        ...         window_size="2h", by="date", closed="both"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬──────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_mean │
        │ ---    ┆ ---                 ┆ ---              │
        │ u32    ┆ datetime[μs]        ┆ f64              │
        ╞════════╪═════════════════════╪══════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ 0.0              │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.5              │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 1.0              │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 2.0              │
        │ …      ┆ …                   ┆ …                │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 20.0             │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 21.0             │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 22.0             │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 23.0             │
        └────────┴─────────────────────┴──────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_mean(
                window_size,
                weights,
                min_periods,
                center,
                by,
                closed,
                warn_if_unsorted,
            )
        )

    @warn_closed_future_change()
    def rolling_sum(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Apply a rolling sum (moving sum) over the values in this array.

        A window of length `window_size` will traverse the array. The values that fill
        this window will (optionally) be multiplied with the weights given by the
        `weight` vector. The resulting values will be aggregated to their sum.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            of dtype `{Date, Datetime}`
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_sum=pl.col("A").rolling_sum(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_sum │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 3.0         │
        │ 3.0 ┆ 5.0         │
        │ 4.0 ┆ 7.0         │
        │ 5.0 ┆ 9.0         │
        │ 6.0 ┆ 11.0        │
        └─────┴─────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_sum=pl.col("A").rolling_sum(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_sum │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.75        │
        │ 3.0 ┆ 2.75        │
        │ 4.0 ┆ 3.75        │
        │ 5.0 ┆ 4.75        │
        │ 6.0 ┆ 5.75        │
        └─────┴─────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_sum=pl.col("A").rolling_sum(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_sum │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 6.0         │
        │ 3.0 ┆ 9.0         │
        │ 4.0 ┆ 12.0        │
        │ 5.0 ┆ 15.0        │
        │ 6.0 ┆ null        │
        └─────┴─────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘

        Compute the rolling sum with the default left closure of temporal windows

        >>> df_temporal.with_columns(
        ...     rolling_row_sum=pl.col("row_nr").rolling_sum(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_sum │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ u32             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null            │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0               │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 1               │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 3               │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 39              │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 41              │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 43              │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 45              │
        └────────┴─────────────────────┴─────────────────┘

        Compute the rolling sum with the closure of windows on both sides

        >>> df_temporal.with_columns(
        ...     rolling_row_sum=pl.col("row_nr").rolling_sum(
        ...         window_size="2h", by="date", closed="both"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_sum │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ u32             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ 0               │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 1               │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 3               │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 6               │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 60              │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 63              │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 66              │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 69              │
        └────────┴─────────────────────┴─────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_sum(
                window_size, weights, min_periods, center, by, closed, warn_if_unsorted
            )
        )

    @warn_closed_future_change()
    def rolling_std(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        ddof: int = 1,
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Compute a rolling standard deviation.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"` means
        the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that determines the
            relative contribution of each value in a window to the output.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        ddof
            "Delta Degrees of Freedom": The divisor for a length N window is N - ddof
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_std=pl.col("A").rolling_std(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_std │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 0.707107    │
        │ 3.0 ┆ 0.707107    │
        │ 4.0 ┆ 0.707107    │
        │ 5.0 ┆ 0.707107    │
        │ 6.0 ┆ 0.707107    │
        └─────┴─────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_std=pl.col("A").rolling_std(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_std │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 0.433013    │
        │ 3.0 ┆ 0.433013    │
        │ 4.0 ┆ 0.433013    │
        │ 5.0 ┆ 0.433013    │
        │ 6.0 ┆ 0.433013    │
        └─────┴─────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_std=pl.col("A").rolling_std(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_std │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.0         │
        │ 3.0 ┆ 1.0         │
        │ 4.0 ┆ 1.0         │
        │ 5.0 ┆ 1.0         │
        │ 6.0 ┆ null        │
        └─────┴─────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘

        Compute the rolling std with the default left closure of temporal windows

        >>> df_temporal.with_columns(
        ...     rolling_row_std=pl.col("row_nr").rolling_std(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_std │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ f64             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null            │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.0             │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 0.707107        │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 0.707107        │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 0.707107        │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 0.707107        │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 0.707107        │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 0.707107        │
        └────────┴─────────────────────┴─────────────────┘

        Compute the rolling std with the closure of windows on both sides

        >>> df_temporal.with_columns(
        ...     rolling_row_std=pl.col("row_nr").rolling_std(
        ...         window_size="2h", by="date", closed="both"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_std │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ f64             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ 0.0             │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.707107        │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 1.0             │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 1.0             │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 1.0             │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 1.0             │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 1.0             │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 1.0             │
        └────────┴─────────────────────┴─────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_std(
                window_size,
                weights,
                min_periods,
                center,
                by,
                closed,
                ddof,
                warn_if_unsorted,
            )
        )

    @warn_closed_future_change()
    def rolling_var(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        ddof: int = 1,
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Compute a rolling variance.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that determines the
            relative contribution of each value in a window to the output.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        ddof
            "Delta Degrees of Freedom": The divisor for a length N window is N - ddof
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_var=pl.col("A").rolling_var(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_var │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 0.5         │
        │ 3.0 ┆ 0.5         │
        │ 4.0 ┆ 0.5         │
        │ 5.0 ┆ 0.5         │
        │ 6.0 ┆ 0.5         │
        └─────┴─────────────┘

        Specify weights to multiply the values in the window with:

        >>> df.with_columns(
        ...     rolling_var=pl.col("A").rolling_var(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_var │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 0.1875      │
        │ 3.0 ┆ 0.1875      │
        │ 4.0 ┆ 0.1875      │
        │ 5.0 ┆ 0.1875      │
        │ 6.0 ┆ 0.1875      │
        └─────┴─────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_var=pl.col("A").rolling_var(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬─────────────┐
        │ A   ┆ rolling_var │
        │ --- ┆ ---         │
        │ f64 ┆ f64         │
        ╞═════╪═════════════╡
        │ 1.0 ┆ null        │
        │ 2.0 ┆ 1.0         │
        │ 3.0 ┆ 1.0         │
        │ 4.0 ┆ 1.0         │
        │ 5.0 ┆ 1.0         │
        │ 6.0 ┆ null        │
        └─────┴─────────────┘

        Create a DataFrame with a datetime column and a row number column

        >>> from datetime import timedelta, datetime
        >>> start = datetime(2001, 1, 1)
        >>> stop = datetime(2001, 1, 2)
        >>> df_temporal = pl.DataFrame(
        ...     {"date": pl.datetime_range(start, stop, "1h", eager=True)}
        ... ).with_row_count()
        >>> df_temporal
        shape: (25, 2)
        ┌────────┬─────────────────────┐
        │ row_nr ┆ date                │
        │ ---    ┆ ---                 │
        │ u32    ┆ datetime[μs]        │
        ╞════════╪═════════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 │
        │ 1      ┆ 2001-01-01 01:00:00 │
        │ 2      ┆ 2001-01-01 02:00:00 │
        │ 3      ┆ 2001-01-01 03:00:00 │
        │ …      ┆ …                   │
        │ 21     ┆ 2001-01-01 21:00:00 │
        │ 22     ┆ 2001-01-01 22:00:00 │
        │ 23     ┆ 2001-01-01 23:00:00 │
        │ 24     ┆ 2001-01-02 00:00:00 │
        └────────┴─────────────────────┘

        Compute the rolling var with the default left closure of temporal windows

        >>> df_temporal.with_columns(
        ...     rolling_row_var=pl.col("row_nr").rolling_var(
        ...         window_size="2h", by="date", closed="left"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_var │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ f64             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ null            │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.0             │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 0.5             │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 0.5             │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 0.5             │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 0.5             │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 0.5             │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 0.5             │
        └────────┴─────────────────────┴─────────────────┘

        Compute the rolling var with the closure of windows on both sides

        >>> df_temporal.with_columns(
        ...     rolling_row_var=pl.col("row_nr").rolling_var(
        ...         window_size="2h", by="date", closed="both"
        ...     )
        ... )
        shape: (25, 3)
        ┌────────┬─────────────────────┬─────────────────┐
        │ row_nr ┆ date                ┆ rolling_row_var │
        │ ---    ┆ ---                 ┆ ---             │
        │ u32    ┆ datetime[μs]        ┆ f64             │
        ╞════════╪═════════════════════╪═════════════════╡
        │ 0      ┆ 2001-01-01 00:00:00 ┆ 0.0             │
        │ 1      ┆ 2001-01-01 01:00:00 ┆ 0.5             │
        │ 2      ┆ 2001-01-01 02:00:00 ┆ 1.0             │
        │ 3      ┆ 2001-01-01 03:00:00 ┆ 1.0             │
        │ …      ┆ …                   ┆ …               │
        │ 21     ┆ 2001-01-01 21:00:00 ┆ 1.0             │
        │ 22     ┆ 2001-01-01 22:00:00 ┆ 1.0             │
        │ 23     ┆ 2001-01-01 23:00:00 ┆ 1.0             │
        │ 24     ┆ 2001-01-02 00:00:00 ┆ 1.0             │
        └────────┴─────────────────────┴─────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_var(
                window_size,
                weights,
                min_periods,
                center,
                by,
                closed,
                ddof,
                warn_if_unsorted,
            )
        )

    @warn_closed_future_change()
    def rolling_median(
        self,
        window_size: int | timedelta | str,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Compute a rolling median.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"` means
        the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic temporal
            size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that determines the
            relative contribution of each value in a window to the output.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_median=pl.col("A").rolling_median(window_size=2),
        ... )
        shape: (6, 2)
        ┌─────┬────────────────┐
        │ A   ┆ rolling_median │
        │ --- ┆ ---            │
        │ f64 ┆ f64            │
        ╞═════╪════════════════╡
        │ 1.0 ┆ null           │
        │ 2.0 ┆ 1.5            │
        │ 3.0 ┆ 2.5            │
        │ 4.0 ┆ 3.5            │
        │ 5.0 ┆ 4.5            │
        │ 6.0 ┆ 5.5            │
        └─────┴────────────────┘

        Specify weights for the values in each window:

        >>> df.with_columns(
        ...     rolling_median=pl.col("A").rolling_median(
        ...         window_size=2, weights=[0.25, 0.75]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬────────────────┐
        │ A   ┆ rolling_median │
        │ --- ┆ ---            │
        │ f64 ┆ f64            │
        ╞═════╪════════════════╡
        │ 1.0 ┆ null           │
        │ 2.0 ┆ 1.5            │
        │ 3.0 ┆ 2.5            │
        │ 4.0 ┆ 3.5            │
        │ 5.0 ┆ 4.5            │
        │ 6.0 ┆ 5.5            │
        └─────┴────────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_median=pl.col("A").rolling_median(window_size=3, center=True),
        ... )
        shape: (6, 2)
        ┌─────┬────────────────┐
        │ A   ┆ rolling_median │
        │ --- ┆ ---            │
        │ f64 ┆ f64            │
        ╞═════╪════════════════╡
        │ 1.0 ┆ null           │
        │ 2.0 ┆ 2.0            │
        │ 3.0 ┆ 3.0            │
        │ 4.0 ┆ 4.0            │
        │ 5.0 ┆ 5.0            │
        │ 6.0 ┆ null           │
        └─────┴────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_median(
                window_size, weights, min_periods, center, by, closed, warn_if_unsorted
            )
        )

    @warn_closed_future_change()
    def rolling_quantile(
        self,
        quantile: float,
        interpolation: RollingInterpolationMethod = "nearest",
        window_size: int | timedelta | str = 2,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
        by: str | None = None,
        closed: ClosedInterval = "left",
        warn_if_unsorted: bool = True,
    ) -> Self:
        """
        Compute a rolling quantile.

        If `by` has not been specified (the default), the window at a given row will
        include the row itself, and the `window_size - 1` elements before it.

        If you pass a `by` column `<t_0, t_1, ..., t_n>`, then `closed="left"`
        means the windows will be:

            - [t_0 - window_size, t_0)
            - [t_1 - window_size, t_1)
            - ...
            - [t_n - window_size, t_n)

        With `closed="right"`, the left endpoint is not included and the right
        endpoint is included.

        Parameters
        ----------
        quantile
            Quantile between 0.0 and 1.0.
        interpolation : {'nearest', 'higher', 'lower', 'midpoint', 'linear'}
            Interpolation method.
        window_size
            The length of the window. Can be a fixed integer size, or a dynamic
            temporal size indicated by a timedelta or the following string language:

            - 1ns   (1 nanosecond)
            - 1us   (1 microsecond)
            - 1ms   (1 millisecond)
            - 1s    (1 second)
            - 1m    (1 minute)
            - 1h    (1 hour)
            - 1d    (1 calendar day)
            - 1w    (1 calendar week)
            - 1mo   (1 calendar month)
            - 1q    (1 calendar quarter)
            - 1y    (1 calendar year)
            - 1i    (1 index count)

            By "calendar day", we mean the corresponding time on the next day
            (which may not be 24 hours, due to daylight savings). Similarly for
            "calendar week", "calendar month", "calendar quarter", and
            "calendar year".

            If a timedelta or the dynamic string language is used, the `by`
            and `closed` arguments must also be set.
        weights
            An optional slice with the same length as the window that determines the
            relative contribution of each value in a window to the output.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window
        by
            If the `window_size` is temporal for instance `"5h"` or `"3s"`, you must
            set the column that will be used to determine the windows. This column must
            be of dtype Datetime or Date.

            .. warning::
                If passed, the column must be sorted in ascending order. Otherwise,
                results will not be correct.
        closed : {'left', 'right', 'both', 'none'}
            Define which sides of the temporal interval are closed (inclusive); only
            applicable if `by` has been set.
        warn_if_unsorted
            Warn if data is not known to be sorted by `by` column (if passed).
            Experimental.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        Notes
        -----
        If you want to compute multiple aggregation statistics over the same dynamic
        window, consider using `rolling` - this method can cache the window size
        computation.

        Examples
        --------
        >>> df = pl.DataFrame({"A": [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]})
        >>> df.with_columns(
        ...     rolling_quantile=pl.col("A").rolling_quantile(
        ...         quantile=0.25, window_size=4
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────────┐
        │ A   ┆ rolling_quantile │
        │ --- ┆ ---              │
        │ f64 ┆ f64              │
        ╞═════╪══════════════════╡
        │ 1.0 ┆ null             │
        │ 2.0 ┆ null             │
        │ 3.0 ┆ null             │
        │ 4.0 ┆ 2.0              │
        │ 5.0 ┆ 3.0              │
        │ 6.0 ┆ 4.0              │
        └─────┴──────────────────┘

        Specify weights for the values in each window:

        >>> df.with_columns(
        ...     rolling_quantile=pl.col("A").rolling_quantile(
        ...         quantile=0.25, window_size=4, weights=[0.2, 0.4, 0.4, 0.2]
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────────┐
        │ A   ┆ rolling_quantile │
        │ --- ┆ ---              │
        │ f64 ┆ f64              │
        ╞═════╪══════════════════╡
        │ 1.0 ┆ null             │
        │ 2.0 ┆ null             │
        │ 3.0 ┆ null             │
        │ 4.0 ┆ 2.0              │
        │ 5.0 ┆ 3.0              │
        │ 6.0 ┆ 4.0              │
        └─────┴──────────────────┘

        Specify weights and interpolation method

        >>> df.with_columns(
        ...     rolling_quantile=pl.col("A").rolling_quantile(
        ...         quantile=0.25,
        ...         window_size=4,
        ...         weights=[0.2, 0.4, 0.4, 0.2],
        ...         interpolation="linear",
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────────┐
        │ A   ┆ rolling_quantile │
        │ --- ┆ ---              │
        │ f64 ┆ f64              │
        ╞═════╪══════════════════╡
        │ 1.0 ┆ null             │
        │ 2.0 ┆ null             │
        │ 3.0 ┆ null             │
        │ 4.0 ┆ 1.625            │
        │ 5.0 ┆ 2.625            │
        │ 6.0 ┆ 3.625            │
        └─────┴──────────────────┘

        Center the values in the window

        >>> df.with_columns(
        ...     rolling_quantile=pl.col("A").rolling_quantile(
        ...         quantile=0.2, window_size=5, center=True
        ...     ),
        ... )
        shape: (6, 2)
        ┌─────┬──────────────────┐
        │ A   ┆ rolling_quantile │
        │ --- ┆ ---              │
        │ f64 ┆ f64              │
        ╞═════╪══════════════════╡
        │ 1.0 ┆ null             │
        │ 2.0 ┆ null             │
        │ 3.0 ┆ 2.0              │
        │ 4.0 ┆ 3.0              │
        │ 5.0 ┆ null             │
        │ 6.0 ┆ null             │
        └─────┴──────────────────┘

        """
        window_size = deprecate_saturating(window_size)
        window_size, min_periods = _prepare_rolling_window_args(
            window_size, min_periods
        )
        return self._from_pyexpr(
            self._pyexpr.rolling_quantile(
                quantile,
                interpolation,
                window_size,
                weights,
                min_periods,
                center,
                by,
                closed,
                warn_if_unsorted,
            )
        )

    def rolling_skew(self, window_size: int, *, bias: bool = True) -> Self:
        """
        Compute a rolling skew.

        The window at a given row includes the row itself and the
        `window_size - 1` elements before it.

        Parameters
        ----------
        window_size
            Integer size of the rolling window.
        bias
            If False, the calculations are corrected for statistical bias.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 4, 2, 9]})
        >>> df.select(pl.col("a").rolling_skew(3))
        shape: (4, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ null     │
        │ null     │
        │ 0.381802 │
        │ 0.47033  │
        └──────────┘

        Note how the values match the following:

        >>> pl.Series([1, 4, 2]).skew(), pl.Series([4, 2, 9]).skew()
        (0.38180177416060584, 0.47033046033698594)

        """
        return self._from_pyexpr(self._pyexpr.rolling_skew(window_size, bias))

    def rolling_map(
        self,
        function: Callable[[Series], Any],
        window_size: int,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
    ) -> Self:
        """
        Compute a custom rolling window function.

        .. warning::
            Computing custom functions is extremely slow. Use specialized rolling
            functions such as :func:`Expr.rolling_sum` if at all possible.

        Parameters
        ----------
        function
            Custom aggregation function.
        window_size
            Size of the window. The window at a given row will include the row
            itself and the `window_size - 1` elements before it.
        weights
            A list of weights with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window.

        Examples
        --------
        >>> from numpy import nansum
        >>> df = pl.DataFrame({"a": [11.0, 2.0, 9.0, float("nan"), 8.0]})
        >>> df.select(pl.col("a").rolling_map(nansum, window_size=3))
        shape: (5, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ null │
        │ null │
        │ 22.0 │
        │ 11.0 │
        │ 17.0 │
        └──────┘

        """
        if min_periods is None:
            min_periods = window_size
        return self._from_pyexpr(
            self._pyexpr.rolling_map(
                function, window_size, weights, min_periods, center
            )
        )

    def abs(self) -> Self:
        """
        Compute absolute values.

        Same as `abs(expr)`.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "A": [-1.0, 0.0, 1.0, 2.0],
        ...     }
        ... )
        >>> df.select(pl.col("A").abs())
        shape: (4, 1)
        ┌─────┐
        │ A   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        │ 0.0 │
        │ 1.0 │
        │ 2.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.abs())

    def rank(
        self,
        method: RankMethod = "average",
        *,
        descending: bool = False,
        seed: int | None = None,
    ) -> Self:
        """
        Assign ranks to data, dealing with ties appropriately.

        Parameters
        ----------
        method : {'average', 'min', 'max', 'dense', 'ordinal', 'random'}
            The method used to assign ranks to tied elements.
            The following methods are available (default is 'average'):

            - 'average' : The average of the ranks that would have been assigned to
              all the tied values is assigned to each value.
            - 'min' : The minimum of the ranks that would have been assigned to all
              the tied values is assigned to each value. (This is also referred to
              as "competition" ranking.)
            - 'max' : The maximum of the ranks that would have been assigned to all
              the tied values is assigned to each value.
            - 'dense' : Like 'min', but the rank of the next highest element is
              assigned the rank immediately after those assigned to the tied
              elements.
            - 'ordinal' : All values are given a distinct rank, corresponding to
              the order that the values occur in the Series.
            - 'random' : Like 'ordinal', but the rank for ties is not dependent
              on the order that the values occur in the Series.
        descending
            Rank in descending order.
        seed
            If `method="random"`, use this as seed.

        Examples
        --------
        The 'average' method:

        >>> df = pl.DataFrame({"a": [3, 6, 1, 1, 6]})
        >>> df.select(pl.col("a").rank())
        shape: (5, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 3.0 │
        │ 4.5 │
        │ 1.5 │
        │ 1.5 │
        │ 4.5 │
        └─────┘

        The 'ordinal' method:

        >>> df = pl.DataFrame({"a": [3, 6, 1, 1, 6]})
        >>> df.select(pl.col("a").rank("ordinal"))
        shape: (5, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 3   │
        │ 4   │
        │ 1   │
        │ 2   │
        │ 5   │
        └─────┘

        Use 'rank' with 'over' to rank within groups:

        >>> df = pl.DataFrame({"a": [1, 1, 2, 2, 2], "b": [6, 7, 5, 14, 11]})
        >>> df.with_columns(pl.col("b").rank().over("a").alias("rank"))
        shape: (5, 3)
        ┌─────┬─────┬──────┐
        │ a   ┆ b   ┆ rank │
        │ --- ┆ --- ┆ ---  │
        │ i64 ┆ i64 ┆ f64  │
        ╞═════╪═════╪══════╡
        │ 1   ┆ 6   ┆ 1.0  │
        │ 1   ┆ 7   ┆ 2.0  │
        │ 2   ┆ 5   ┆ 1.0  │
        │ 2   ┆ 14  ┆ 3.0  │
        │ 2   ┆ 11  ┆ 2.0  │
        └─────┴─────┴──────┘

        """
        return self._from_pyexpr(self._pyexpr.rank(method, descending, seed))

    def diff(self, n: int = 1, null_behavior: NullBehavior = "ignore") -> Self:
        """
        Calculate the first discrete difference between shifted items.

        Parameters
        ----------
        n
            Number of slots to shift.
        null_behavior : {'ignore', 'drop'}
            How to handle null values.

        Examples
        --------
        >>> df = pl.DataFrame({"int": [20, 10, 30, 25, 35]})
        >>> df.with_columns(change=pl.col("int").diff())
        shape: (5, 2)
        ┌─────┬────────┐
        │ int ┆ change │
        │ --- ┆ ---    │
        │ i64 ┆ i64    │
        ╞═════╪════════╡
        │ 20  ┆ null   │
        │ 10  ┆ -10    │
        │ 30  ┆ 20     │
        │ 25  ┆ -5     │
        │ 35  ┆ 10     │
        └─────┴────────┘

        >>> df.with_columns(change=pl.col("int").diff(n=2))
        shape: (5, 2)
        ┌─────┬────────┐
        │ int ┆ change │
        │ --- ┆ ---    │
        │ i64 ┆ i64    │
        ╞═════╪════════╡
        │ 20  ┆ null   │
        │ 10  ┆ null   │
        │ 30  ┆ 10     │
        │ 25  ┆ 15     │
        │ 35  ┆ 5      │
        └─────┴────────┘

        >>> df.select(pl.col("int").diff(n=2, null_behavior="drop").alias("diff"))
        shape: (3, 1)
        ┌──────┐
        │ diff │
        │ ---  │
        │ i64  │
        ╞══════╡
        │ 10   │
        │ 15   │
        │ 5    │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.diff(n, null_behavior))

    def pct_change(self, n: int | IntoExprColumn = 1) -> Self:
        """
        Computes percentage change between values.

        Percentage change (as fraction) between current element and most-recent
        non-null element at least `n` period(s) before the current element.

        Computes the change from the previous row by default.

        Parameters
        ----------
        n
            periods to shift for forming percent change.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "a": [10, 11, 12, None, 12],
        ...     }
        ... )
        >>> df.with_columns(pl.col("a").pct_change().alias("pct_change"))
        shape: (5, 2)
        ┌──────┬────────────┐
        │ a    ┆ pct_change │
        │ ---  ┆ ---        │
        │ i64  ┆ f64        │
        ╞══════╪════════════╡
        │ 10   ┆ null       │
        │ 11   ┆ 0.1        │
        │ 12   ┆ 0.090909   │
        │ null ┆ 0.0        │
        │ 12   ┆ 0.0        │
        └──────┴────────────┘

        """
        n = parse_as_expression(n)
        return self._from_pyexpr(self._pyexpr.pct_change(n))

    def skew(self, *, bias: bool = True) -> Self:
        r"""
        Compute the sample skewness of a data set.

        For normally distributed data, the skewness should be about zero. For
        unimodal continuous distributions, a skewness value greater than zero means
        that there is more weight in the right tail of the distribution. The
        function `skewtest` can be used to determine if the skewness value
        is close enough to zero, statistically speaking.


        See scipy.stats for more information.

        Parameters
        ----------
        bias : bool, optional
            If False, the calculations are corrected for statistical bias.

        Notes
        -----
        The sample skewness is computed as the Fisher-Pearson coefficient
        of skewness, i.e.

        .. math:: g_1=\frac{m_3}{m_2^{3/2}}

        where

        .. math:: m_i=\frac{1}{N}\sum_{n=1}^N(x[n]-\bar{x})^i

        is the biased sample :math:`i\texttt{th}` central moment, and
        :math:`\bar{x}` is
        the sample mean.  If `bias` is False, the calculations are
        corrected for bias and the value computed is the adjusted
        Fisher-Pearson standardized moment coefficient, i.e.

        .. math::
            G_1 = \frac{k_3}{k_2^{3/2}} = \frac{\sqrt{N(N-1)}}{N-2}\frac{m_3}{m_2^{3/2}}

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 2, 1]})
        >>> df.select(pl.col("a").skew())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.343622 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.skew(bias))

    def kurtosis(self, *, fisher: bool = True, bias: bool = True) -> Self:
        """
        Compute the kurtosis (Fisher or Pearson) of a dataset.

        Kurtosis is the fourth central moment divided by the square of the
        variance. If Fisher's definition is used, then 3.0 is subtracted from
        the result to give 0.0 for a normal distribution.
        If bias is False then the kurtosis is calculated using k statistics to
        eliminate bias coming from biased moment estimators.

        See scipy.stats for more information

        Parameters
        ----------
        fisher : bool, optional
            If True, Fisher's definition is used (normal ==> 0.0). If False,
            Pearson's definition is used (normal ==> 3.0).
        bias : bool, optional
            If False, the calculations are corrected for statistical bias.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 2, 1]})
        >>> df.select(pl.col("a").kurtosis())
        shape: (1, 1)
        ┌───────────┐
        │ a         │
        │ ---       │
        │ f64       │
        ╞═══════════╡
        │ -1.153061 │
        └───────────┘

        """
        return self._from_pyexpr(self._pyexpr.kurtosis(fisher, bias))

    def clip(
        self,
        lower_bound: NumericLiteral | TemporalLiteral | IntoExprColumn | None = None,
        upper_bound: NumericLiteral | TemporalLiteral | IntoExprColumn | None = None,
    ) -> Self:
        """
        Set values outside the given boundaries to the boundary value.

        Parameters
        ----------
        lower_bound
            Lower bound. Accepts expression input.
            Non-expression inputs are parsed as literals.
        upper_bound
            Upper bound. Accepts expression input.
            Non-expression inputs are parsed as literals.

        See Also
        --------
        when

        Notes
        -----
        This method only works for numeric and temporal columns. To clip other data
        types, consider writing a `when-then-otherwise` expression. See :func:`when`.

        Examples
        --------
        Specifying both a lower and upper bound:

        >>> df = pl.DataFrame({"a": [-50, 5, 50, None]})
        >>> df.with_columns(clip=pl.col("a").clip(1, 10))
        shape: (4, 2)
        ┌──────┬──────┐
        │ a    ┆ clip │
        │ ---  ┆ ---  │
        │ i64  ┆ i64  │
        ╞══════╪══════╡
        │ -50  ┆ 1    │
        │ 5    ┆ 5    │
        │ 50   ┆ 10   │
        │ null ┆ null │
        └──────┴──────┘

        Specifying only a single bound:

        >>> df.with_columns(clip=pl.col("a").clip(upper_bound=10))
        shape: (4, 2)
        ┌──────┬──────┐
        │ a    ┆ clip │
        │ ---  ┆ ---  │
        │ i64  ┆ i64  │
        ╞══════╪══════╡
        │ -50  ┆ -50  │
        │ 5    ┆ 5    │
        │ 50   ┆ 10   │
        │ null ┆ null │
        └──────┴──────┘

        """
        if lower_bound is not None:
            lower_bound = parse_as_expression(lower_bound, str_as_lit=True)
        if upper_bound is not None:
            upper_bound = parse_as_expression(upper_bound, str_as_lit=True)
        return self._from_pyexpr(self._pyexpr.clip(lower_bound, upper_bound))

    def lower_bound(self) -> Self:
        """
        Calculate the lower bound.

        Returns a unit Series with the lowest value possible for the dtype of this
        expression.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 2, 1]})
        >>> df.select(pl.col("a").lower_bound())
        shape: (1, 1)
        ┌──────────────────────┐
        │ a                    │
        │ ---                  │
        │ i64                  │
        ╞══════════════════════╡
        │ -9223372036854775808 │
        └──────────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.lower_bound())

    def upper_bound(self) -> Self:
        """
        Calculate the upper bound.

        Returns a unit Series with the highest value possible for the dtype of this
        expression.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3, 2, 1]})
        >>> df.select(pl.col("a").upper_bound())
        shape: (1, 1)
        ┌─────────────────────┐
        │ a                   │
        │ ---                 │
        │ i64                 │
        ╞═════════════════════╡
        │ 9223372036854775807 │
        └─────────────────────┘

        """
        return self._from_pyexpr(self._pyexpr.upper_bound())

    def sign(self) -> Self:
        """
        Compute the element-wise indication of the sign.

        The returned values can be -1, 0, or 1:

        * -1 if x  < 0.
        *  0 if x == 0.
        *  1 if x  > 0.

        (null values are preserved as-is).

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-9.0, -0.0, 0.0, 4.0, None]})
        >>> df.select(pl.col("a").sign())
        shape: (5, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ i64  │
        ╞══════╡
        │ -1   │
        │ 0    │
        │ 0    │
        │ 1    │
        │ null │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.sign())

    def sin(self) -> Self:
        """
        Compute the element-wise value for the sine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.0]})
        >>> df.select(pl.col("a").sin())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.sin())

    def cos(self) -> Self:
        """
        Compute the element-wise value for the cosine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.0]})
        >>> df.select(pl.col("a").cos())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 1.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.cos())

    def tan(self) -> Self:
        """
        Compute the element-wise value for the tangent.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").tan().round(2))
        shape: (1, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ 1.56 │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.tan())

    def cot(self) -> Self:
        """
        Compute the element-wise value for the cotangent.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").cot().round(2))
        shape: (1, 1)
        ┌──────┐
        │ a    │
        │ ---  │
        │ f64  │
        ╞══════╡
        │ 0.64 │
        └──────┘

        """
        return self._from_pyexpr(self._pyexpr.cot())

    def arcsin(self) -> Self:
        """
        Compute the element-wise value for the inverse sine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").arcsin())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.570796 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.arcsin())

    def arccos(self) -> Self:
        """
        Compute the element-wise value for the inverse cosine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [0.0]})
        >>> df.select(pl.col("a").arccos())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.570796 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.arccos())

    def arctan(self) -> Self:
        """
        Compute the element-wise value for the inverse tangent.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").arctan())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.785398 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.arctan())

    def sinh(self) -> Self:
        """
        Compute the element-wise value for the hyperbolic sine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").sinh())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.175201 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.sinh())

    def cosh(self) -> Self:
        """
        Compute the element-wise value for the hyperbolic cosine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").cosh())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.543081 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.cosh())

    def tanh(self) -> Self:
        """
        Compute the element-wise value for the hyperbolic tangent.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").tanh())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.761594 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.tanh())

    def arcsinh(self) -> Self:
        """
        Compute the element-wise value for the inverse hyperbolic sine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").arcsinh())
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.881374 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.arcsinh())

    def arccosh(self) -> Self:
        """
        Compute the element-wise value for the inverse hyperbolic cosine.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").arccosh())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ 0.0 │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arccosh())

    def arctanh(self) -> Self:
        """
        Compute the element-wise value for the inverse hyperbolic tangent.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1.0]})
        >>> df.select(pl.col("a").arctanh())
        shape: (1, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ f64 │
        ╞═════╡
        │ inf │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.arctanh())

    def degrees(self) -> Self:
        """
        Convert from radians to degrees.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> import math
        >>> df = pl.DataFrame({"a": [x * math.pi for x in range(-4, 5)]})
        >>> df.select(pl.col("a").degrees())
        shape: (9, 1)
        ┌────────┐
        │ a      │
        │ ---    │
        │ f64    │
        ╞════════╡
        │ -720.0 │
        │ -540.0 │
        │ -360.0 │
        │ -180.0 │
        │ 0.0    │
        │ 180.0  │
        │ 360.0  │
        │ 540.0  │
        │ 720.0  │
        └────────┘
        """
        return self._from_pyexpr(self._pyexpr.degrees())

    def radians(self) -> Self:
        """
        Convert from degrees to radians.

        Returns
        -------
        Expr
            Expression of data type :class:`Float64`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [-720, -540, -360, -180, 0, 180, 360, 540, 720]})
        >>> df.select(pl.col("a").radians())
        shape: (9, 1)
        ┌────────────┐
        │ a          │
        │ ---        │
        │ f64        │
        ╞════════════╡
        │ -12.566371 │
        │ -9.424778  │
        │ -6.283185  │
        │ -3.141593  │
        │ 0.0        │
        │ 3.141593   │
        │ 6.283185   │
        │ 9.424778   │
        │ 12.566371  │
        └────────────┘
        """
        return self._from_pyexpr(self._pyexpr.radians())

    def reshape(self, dimensions: tuple[int, ...]) -> Self:
        """
        Reshape this Expr to a flat Series or a Series of Lists.

        Parameters
        ----------
        dimensions
            Tuple of the dimension sizes. If a -1 is used in any of the dimensions, that
            dimension is inferred.

        Returns
        -------
        Expr
            If a single dimension is given, results in an expression of the original
            data type.
            If a multiple dimensions are given, results in an expression of data type
            :class:`List` with shape (rows, cols).

        Examples
        --------
        >>> df = pl.DataFrame({"foo": [1, 2, 3, 4, 5, 6, 7, 8, 9]})
        >>> df.select(pl.col("foo").reshape((3, 3)))
        shape: (3, 1)
        ┌───────────┐
        │ foo       │
        │ ---       │
        │ list[i64] │
        ╞═══════════╡
        │ [1, 2, 3] │
        │ [4, 5, 6] │
        │ [7, 8, 9] │
        └───────────┘

        See Also
        --------
        Expr.list.explode : Explode a list column.

        """
        return self._from_pyexpr(self._pyexpr.reshape(dimensions))

    def shuffle(self, seed: int | None = None) -> Self:
        """
        Shuffle the contents of this expression.

        Parameters
        ----------
        seed
            Seed for the random number generator. If set to None (default), a
            random seed is generated each time the shuffle is called.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").shuffle(seed=1))
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 2   │
        │ 1   │
        │ 3   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.shuffle(seed))

    def sample(
        self,
        n: int | IntoExprColumn | None = None,
        *,
        fraction: float | IntoExprColumn | None = None,
        with_replacement: bool = False,
        shuffle: bool = False,
        seed: int | None = None,
    ) -> Self:
        """
        Sample from this expression.

        Parameters
        ----------
        n
            Number of items to return. Cannot be used with `fraction`. Defaults to 1 if
            `fraction` is None.
        fraction
            Fraction of items to return. Cannot be used with `n`.
        with_replacement
            Allow values to be sampled more than once.
        shuffle
            Shuffle the order of sampled data points.
        seed
            Seed for the random number generator. If set to None (default), a
            random seed is generated for each sample operation.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").sample(fraction=1.0, with_replacement=True, seed=1))
        shape: (3, 1)
        ┌─────┐
        │ a   │
        │ --- │
        │ i64 │
        ╞═════╡
        │ 3   │
        │ 1   │
        │ 1   │
        └─────┘

        """
        if n is not None and fraction is not None:
            raise ValueError("cannot specify both `n` and `fraction`")

        if fraction is not None:
            fraction = parse_as_expression(fraction)
            return self._from_pyexpr(
                self._pyexpr.sample_frac(fraction, with_replacement, shuffle, seed)
            )

        if n is None:
            n = 1
        n = parse_as_expression(n)
        return self._from_pyexpr(
            self._pyexpr.sample_n(n, with_replacement, shuffle, seed)
        )

    @deprecate_nonkeyword_arguments(version="0.19.10")
    def ewm_mean(
        self,
        com: float | None = None,
        span: float | None = None,
        half_life: float | None = None,
        alpha: float | None = None,
        *,
        adjust: bool = True,
        min_periods: int = 1,
        ignore_nulls: bool = True,
    ) -> Self:
        r"""
        Exponentially-weighted moving average.

        Parameters
        ----------
        com
            Specify decay in terms of center of mass, :math:`\gamma`, with

                .. math::
                    \alpha = \frac{1}{1 + \gamma} \; \forall \; \gamma \geq 0
        span
            Specify decay in terms of span, :math:`\theta`, with

                .. math::
                    \alpha = \frac{2}{\theta + 1} \; \forall \; \theta \geq 1
        half_life
            Specify decay in terms of half-life, :math:`\lambda`, with

                .. math::
                    \alpha = 1 - \exp \left\{ \frac{ -\ln(2) }{ \lambda } \right\} \;
                    \forall \; \lambda > 0
        alpha
            Specify smoothing factor alpha directly, :math:`0 < \alpha \leq 1`.
        adjust
            Divide by decaying adjustment factor in beginning periods to account for
            imbalance in relative weightings

                - When `adjust=True` the EW function is calculated
                  using weights :math:`w_i = (1 - \alpha)^i`
                - When `adjust=False` the EW function is calculated
                  recursively by

                  .. math::
                    y_0 &= x_0 \\
                    y_t &= (1 - \alpha)y_{t - 1} + \alpha x_t
        min_periods
            Minimum number of observations in window required to have a value
            (otherwise result is null).
        ignore_nulls
            Ignore missing values when calculating weights.

                - When `ignore_nulls=False` (default), weights are based on absolute
                  positions.
                  For example, the weights of :math:`x_0` and :math:`x_2` used in
                  calculating the final weighted average of
                  [:math:`x_0`, None, :math:`x_2`] are
                  :math:`(1-\alpha)^2` and :math:`1` if `adjust=True`, and
                  :math:`(1-\alpha)^2` and :math:`\alpha` if `adjust=False`.

                - When `ignore_nulls=True`, weights are based
                  on relative positions. For example, the weights of
                  :math:`x_0` and :math:`x_2` used in calculating the final weighted
                  average of [:math:`x_0`, None, :math:`x_2`] are
                  :math:`1-\alpha` and :math:`1` if `adjust=True`,
                  and :math:`1-\alpha` and :math:`\alpha` if `adjust=False`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").ewm_mean(com=1))
        shape: (3, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.0      │
        │ 1.666667 │
        │ 2.428571 │
        └──────────┘

        """
        alpha = _prepare_alpha(com, span, half_life, alpha)
        return self._from_pyexpr(
            self._pyexpr.ewm_mean(alpha, adjust, min_periods, ignore_nulls)
        )

    @deprecate_nonkeyword_arguments(version="0.19.10")
    def ewm_std(
        self,
        com: float | None = None,
        span: float | None = None,
        half_life: float | None = None,
        alpha: float | None = None,
        *,
        adjust: bool = True,
        bias: bool = False,
        min_periods: int = 1,
        ignore_nulls: bool = True,
    ) -> Self:
        r"""
        Exponentially-weighted moving standard deviation.

        Parameters
        ----------
        com
            Specify decay in terms of center of mass, :math:`\gamma`, with

                .. math::
                    \alpha = \frac{1}{1 + \gamma} \; \forall \; \gamma \geq 0
        span
            Specify decay in terms of span, :math:`\theta`, with

                .. math::
                    \alpha = \frac{2}{\theta + 1} \; \forall \; \theta \geq 1
        half_life
            Specify decay in terms of half-life, :math:`\lambda`, with

                .. math::
                    \alpha = 1 - \exp \left\{ \frac{ -\ln(2) }{ \lambda } \right\} \;
                    \forall \; \lambda > 0
        alpha
            Specify smoothing factor alpha directly, :math:`0 < \alpha \leq 1`.
        adjust
            Divide by decaying adjustment factor in beginning periods to account for
            imbalance in relative weightings

                - When `adjust=True` the EW function is calculated
                  using weights :math:`w_i = (1 - \alpha)^i`
                - When `adjust=False` the EW function is calculated
                  recursively by

                  .. math::
                    y_0 &= x_0 \\
                    y_t &= (1 - \alpha)y_{t - 1} + \alpha x_t
        bias
            When `bias=False`, apply a correction to make the estimate statistically
            unbiased.
        min_periods
            Minimum number of observations in window required to have a value
            (otherwise result is null).
        ignore_nulls
            Ignore missing values when calculating weights.

                - When `ignore_nulls=False` (default), weights are based on absolute
                  positions.
                  For example, the weights of :math:`x_0` and :math:`x_2` used in
                  calculating the final weighted average of
                  [:math:`x_0`, None, :math:`x_2`] are
                  :math:`(1-\alpha)^2` and :math:`1` if `adjust=True`, and
                  :math:`(1-\alpha)^2` and :math:`\alpha` if `adjust=False`.

                - When `ignore_nulls=True`, weights are based
                  on relative positions. For example, the weights of
                  :math:`x_0` and :math:`x_2` used in calculating the final weighted
                  average of [:math:`x_0`, None, :math:`x_2`] are
                  :math:`1-\alpha` and :math:`1` if `adjust=True`,
                  and :math:`1-\alpha` and :math:`\alpha` if `adjust=False`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").ewm_std(com=1))
        shape: (3, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.0      │
        │ 0.707107 │
        │ 0.963624 │
        └──────────┘

        """
        alpha = _prepare_alpha(com, span, half_life, alpha)
        return self._from_pyexpr(
            self._pyexpr.ewm_std(alpha, adjust, bias, min_periods, ignore_nulls)
        )

    @deprecate_nonkeyword_arguments(version="0.19.10")
    def ewm_var(
        self,
        com: float | None = None,
        span: float | None = None,
        half_life: float | None = None,
        alpha: float | None = None,
        *,
        adjust: bool = True,
        bias: bool = False,
        min_periods: int = 1,
        ignore_nulls: bool = True,
    ) -> Self:
        r"""
        Exponentially-weighted moving variance.

        Parameters
        ----------
        com
            Specify decay in terms of center of mass, :math:`\gamma`, with

                .. math::
                    \alpha = \frac{1}{1 + \gamma} \; \forall \; \gamma \geq 0
        span
            Specify decay in terms of span, :math:`\theta`, with

                .. math::
                    \alpha = \frac{2}{\theta + 1} \; \forall \; \theta \geq 1
        half_life
            Specify decay in terms of half-life, :math:`\lambda`, with

                .. math::
                    \alpha = 1 - \exp \left\{ \frac{ -\ln(2) }{ \lambda } \right\} \;
                    \forall \; \lambda > 0
        alpha
            Specify smoothing factor alpha directly, :math:`0 < \alpha \leq 1`.
        adjust
            Divide by decaying adjustment factor in beginning periods to account for
            imbalance in relative weightings

                - When `adjust=True` the EW function is calculated
                  using weights :math:`w_i = (1 - \alpha)^i`
                - When `adjust=False` the EW function is calculated
                  recursively by

                  .. math::
                    y_0 &= x_0 \\
                    y_t &= (1 - \alpha)y_{t - 1} + \alpha x_t
        bias
            When `bias=False`, apply a correction to make the estimate statistically
            unbiased.
        min_periods
            Minimum number of observations in window required to have a value
            (otherwise result is null).
        ignore_nulls
            Ignore missing values when calculating weights.

                - When `ignore_nulls=False` (default), weights are based on absolute
                  positions.
                  For example, the weights of :math:`x_0` and :math:`x_2` used in
                  calculating the final weighted average of
                  [:math:`x_0`, None, :math:`x_2`] are
                  :math:`(1-\alpha)^2` and :math:`1` if `adjust=True`, and
                  :math:`(1-\alpha)^2` and :math:`\alpha` if `adjust=False`.

                - When `ignore_nulls=True`, weights are based
                  on relative positions. For example, the weights of
                  :math:`x_0` and :math:`x_2` used in calculating the final weighted
                  average of [:math:`x_0`, None, :math:`x_2`] are
                  :math:`1-\alpha` and :math:`1` if `adjust=True`,
                  and :math:`1-\alpha` and :math:`\alpha` if `adjust=False`.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").ewm_var(com=1))
        shape: (3, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.0      │
        │ 0.5      │
        │ 0.928571 │
        └──────────┘

        """
        alpha = _prepare_alpha(com, span, half_life, alpha)
        return self._from_pyexpr(
            self._pyexpr.ewm_var(alpha, adjust, bias, min_periods, ignore_nulls)
        )

    def extend_constant(self, value: PythonLiteral | None, n: int) -> Self:
        """
        Extremely fast method for extending the Series with 'n' copies of a value.

        Parameters
        ----------
        value
            A constant literal value (not an expression) with which to extend the
            expression result Series; can pass None to extend with nulls.
        n
            The number of additional values that will be added.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1, 2, 3]})
        >>> df.select((pl.col("values") - 1).extend_constant(99, n=2))
        shape: (5, 1)
        ┌────────┐
        │ values │
        │ ---    │
        │ i64    │
        ╞════════╡
        │ 0      │
        │ 1      │
        │ 2      │
        │ 99     │
        │ 99     │
        └────────┘

        """
        if isinstance(value, Expr):
            raise TypeError(f"`value` must be a supported literal; found {value!r}")

        return self._from_pyexpr(self._pyexpr.extend_constant(value, n))

    @deprecate_renamed_parameter("multithreaded", "parallel", version="0.19.0")
    def value_counts(self, *, sort: bool = False, parallel: bool = False) -> Self:
        """
        Count the occurrences of unique values.

        Parameters
        ----------
        sort
            Sort the output by count in descending order.
            If set to `False` (default), the order of the output is random.
        parallel
            Execute the computation in parallel.

            .. note::
                This option should likely not be enabled in a group by context,
                as the computation is already parallelized per group.

        Returns
        -------
        Expr
            Expression of data type :class:`Struct` with mapping of unique values to
            their count.

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {"color": ["red", "blue", "red", "green", "blue", "blue"]}
        ... )
        >>> df.select(pl.col("color").value_counts())  # doctest: +IGNORE_RESULT
        shape: (3, 1)
        ┌─────────────┐
        │ color       │
        │ ---         │
        │ struct[2]   │
        ╞═════════════╡
        │ {"red",2}   │
        │ {"green",1} │
        │ {"blue",3}  │
        └─────────────┘

        Sort the output by count.

        >>> df.select(pl.col("color").value_counts(sort=True))
        shape: (3, 1)
        ┌─────────────┐
        │ color       │
        │ ---         │
        │ struct[2]   │
        ╞═════════════╡
        │ {"blue",3}  │
        │ {"red",2}   │
        │ {"green",1} │
        └─────────────┘

        """
        return self._from_pyexpr(self._pyexpr.value_counts(sort, parallel))

    def unique_counts(self) -> Self:
        """
        Return a count of the unique values in the order of appearance.

        This method differs from `value_counts` in that it does not return the
        values, only the counts and might be faster

        Examples
        --------
        >>> df = pl.DataFrame(
        ...     {
        ...         "id": ["a", "b", "b", "c", "c", "c"],
        ...     }
        ... )
        >>> df.select(
        ...     [
        ...         pl.col("id").unique_counts(),
        ...     ]
        ... )
        shape: (3, 1)
        ┌─────┐
        │ id  │
        │ --- │
        │ u32 │
        ╞═════╡
        │ 1   │
        │ 2   │
        │ 3   │
        └─────┘

        """
        return self._from_pyexpr(self._pyexpr.unique_counts())

    def log(self, base: float = math.e) -> Self:
        """
        Compute the logarithm to a given base.

        Parameters
        ----------
        base
            Given base, defaults to `e`

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").log(base=2))
        shape: (3, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.0      │
        │ 1.0      │
        │ 1.584963 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.log(base))

    def log1p(self) -> Self:
        """
        Compute the natural logarithm of each element plus one.

        This computes `log(1 + x)` but is more numerically stable for `x` close to zero.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").log1p())
        shape: (3, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 0.693147 │
        │ 1.098612 │
        │ 1.386294 │
        └──────────┘

        """
        return self._from_pyexpr(self._pyexpr.log1p())

    def entropy(self, base: float = math.e, *, normalize: bool = True) -> Self:
        """
        Computes the entropy.

        Uses the formula `-sum(pk * log(pk)` where `pk` are discrete probabilities.

        Parameters
        ----------
        base
            Given base, defaults to `e`
        normalize
            Normalize pk if it doesn't sum to 1.

        Examples
        --------
        >>> df = pl.DataFrame({"a": [1, 2, 3]})
        >>> df.select(pl.col("a").entropy(base=2))
        shape: (1, 1)
        ┌──────────┐
        │ a        │
        │ ---      │
        │ f64      │
        ╞══════════╡
        │ 1.459148 │
        └──────────┘
        >>> df.select(pl.col("a").entropy(base=2, normalize=False))
        shape: (1, 1)
        ┌───────────┐
        │ a         │
        │ ---       │
        │ f64       │
        ╞═══════════╡
        │ -6.754888 │
        └───────────┘

        """
        return self._from_pyexpr(self._pyexpr.entropy(base, normalize))

    def cumulative_eval(
        self, expr: Expr, min_periods: int = 1, *, parallel: bool = False
    ) -> Self:
        """
        Run an expression over a sliding window that increases `1` slot every iteration.

        Parameters
        ----------
        expr
            Expression to evaluate
        min_periods
            Number of valid values there should be in the window before the expression
            is evaluated. valid values = `length - null_count`
        parallel
            Run in parallel. Don't do this in a group by or another operation that
            already has much parallelization.

        Warnings
        --------
        This functionality is experimental and may change without it being considered a
        breaking change.

        This can be really slow as it can have `O(n^2)` complexity. Don't use this
        for operations that visit all elements.

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1, 2, 3, 4, 5]})
        >>> df.select(
        ...     [
        ...         pl.col("values").cumulative_eval(
        ...             pl.element().first() - pl.element().last() ** 2
        ...         )
        ...     ]
        ... )
        shape: (5, 1)
        ┌────────┐
        │ values │
        │ ---    │
        │ f64    │
        ╞════════╡
        │ 0.0    │
        │ -3.0   │
        │ -8.0   │
        │ -15.0  │
        │ -24.0  │
        └────────┘

        """
        return self._from_pyexpr(
            self._pyexpr.cumulative_eval(expr._pyexpr, min_periods, parallel)
        )

    def set_sorted(self, *, descending: bool = False) -> Self:
        """
        Flags the expression as 'sorted'.

        Enables downstream code to user fast paths for sorted arrays.

        Parameters
        ----------
        descending
            Whether the `Series` order is descending.

        Warnings
        --------
        This can lead to incorrect results if this `Series` is not sorted!!
        Use with care!

        Examples
        --------
        >>> df = pl.DataFrame({"values": [1, 2, 3]})
        >>> df.select(pl.col("values").set_sorted().max())
        shape: (1, 1)
        ┌────────┐
        │ values │
        │ ---    │
        │ i64    │
        ╞════════╡
        │ 3      │
        └────────┘

        """
        return self._from_pyexpr(self._pyexpr.set_sorted_flag(descending))

    def shrink_dtype(self) -> Self:
        """
        Shrink numeric columns to the minimal required datatype.

        Shrink to the dtype needed to fit the extrema of this [`Series`].
        This can be used to reduce memory pressure.

        Examples
        --------
        >>> pl.DataFrame(
        ...     {
        ...         "a": [1, 2, 3],
        ...         "b": [1, 2, 2 << 32],
        ...         "c": [-1, 2, 1 << 30],
        ...         "d": [-112, 2, 112],
        ...         "e": [-112, 2, 129],
        ...         "f": ["a", "b", "c"],
        ...         "g": [0.1, 1.32, 0.12],
        ...         "h": [True, None, False],
        ...     }
        ... ).select(pl.all().shrink_dtype())
        shape: (3, 8)
        ┌─────┬────────────┬────────────┬──────┬──────┬─────┬──────┬───────┐
        │ a   ┆ b          ┆ c          ┆ d    ┆ e    ┆ f   ┆ g    ┆ h     │
        │ --- ┆ ---        ┆ ---        ┆ ---  ┆ ---  ┆ --- ┆ ---  ┆ ---   │
        │ i8  ┆ i64        ┆ i32        ┆ i8   ┆ i16  ┆ str ┆ f32  ┆ bool  │
        ╞═════╪════════════╪════════════╪══════╪══════╪═════╪══════╪═══════╡
        │ 1   ┆ 1          ┆ -1         ┆ -112 ┆ -112 ┆ a   ┆ 0.1  ┆ true  │
        │ 2   ┆ 2          ┆ 2          ┆ 2    ┆ 2    ┆ b   ┆ 1.32 ┆ null  │
        │ 3   ┆ 8589934592 ┆ 1073741824 ┆ 112  ┆ 129  ┆ c   ┆ 0.12 ┆ false │
        └─────┴────────────┴────────────┴──────┴──────┴─────┴──────┴───────┘

        """
        return self._from_pyexpr(self._pyexpr.shrink_dtype())

    @deprecate_function(
        "This method now does nothing. It has been superseded by the"
        " `comm_subexpr_elim` setting on `LazyFrame.collect`, which automatically"
        " caches expressions that are equal.",
        version="0.18.9",
    )
    def cache(self) -> Self:
        """
        Cache this expression so that it only is executed once per context.

        .. deprecated:: 0.18.9
            This method now does nothing. It has been superseded by the
            `comm_subexpr_elim` setting on `LazyFrame.collect`, which automatically
            caches expressions that are equal.

        """
        return self

    def replace(
        self,
        mapping: dict[Any, Any],
        *,
        default: Any = no_default,
        return_dtype: PolarsDataType | None = None,
    ) -> Self:
        """
        Replace values according to the given mapping.

        Needs a global string cache for lazily evaluated queries on columns of
        type `Categorical`.

        Parameters
        ----------
        mapping
            Mapping of values to their replacement.
        default
            Value to use when the mapping does not contain the lookup value.
            Defaults to keeping the original value. Accepts expression input.
            Non-expression inputs are parsed as literals.
        return_dtype
            Set return dtype to override automatic return dtype determination.

        See Also
        --------
        str.replace

        Examples
        --------
        Replace a single value by another value. Values not in the mapping remain
        unchanged.

        >>> df = pl.DataFrame({"a": [1, 2, 2, 3]})
        >>> df.with_columns(pl.col("a").replace({2: 100}).alias("replaced"))
        shape: (4, 2)
        ┌─────┬──────────┐
        │ a   ┆ replaced │
        │ --- ┆ ---      │
        │ i64 ┆ i64      │
        ╞═════╪══════════╡
        │ 1   ┆ 1        │
        │ 2   ┆ 100      │
        │ 2   ┆ 100      │
        │ 3   ┆ 3        │
        └─────┴──────────┘

        Replace multiple values. Specify a default to set values not in the given map
        to the default value.

        >>> df = pl.DataFrame({"country_code": ["FR", "ES", "DE", None]})
        >>> country_code_map = {
        ...     "CA": "Canada",
        ...     "DE": "Germany",
        ...     "FR": "France",
        ...     None: "unspecified",
        ... }
        >>> df.with_columns(
        ...     pl.col("country_code")
        ...     .replace(country_code_map, default=None)
        ...     .alias("replaced")
        ... )
        shape: (4, 2)
        ┌──────────────┬─────────────┐
        │ country_code ┆ replaced    │
        │ ---          ┆ ---         │
        │ str          ┆ str         │
        ╞══════════════╪═════════════╡
        │ FR           ┆ France      │
        │ ES           ┆ null        │
        │ DE           ┆ Germany     │
        │ null         ┆ unspecified │
        └──────────────┴─────────────┘

        The return type can be overridden with the `return_dtype` argument.

        >>> df = df.with_row_count()
        >>> df.select(
        ...     "row_nr",
        ...     pl.col("row_nr")
        ...     .replace({1: 10, 2: 20}, default=0, return_dtype=pl.UInt8)
        ...     .alias("replaced"),
        ... )
        shape: (4, 2)
        ┌────────┬──────────┐
        │ row_nr ┆ replaced │
        │ ---    ┆ ---      │
        │ u32    ┆ u8       │
        ╞════════╪══════════╡
        │ 0      ┆ 0        │
        │ 1      ┆ 10       │
        │ 2      ┆ 20       │
        │ 3      ┆ 0        │
        └────────┴──────────┘

        To reference other columns as a `default` value, a struct column must be
        constructed first. The first field must be the column in which values are
        replaced. The other columns can be used in the default expression.

        >>> df.with_columns(
        ...     pl.struct("country_code", "row_nr")
        ...     .replace(
        ...         mapping=country_code_map,
        ...         default=pl.col("row_nr").cast(pl.Utf8),
        ...     )
        ...     .alias("replaced")
        ... )
        shape: (4, 3)
        ┌────────┬──────────────┬─────────────┐
        │ row_nr ┆ country_code ┆ replaced    │
        │ ---    ┆ ---          ┆ ---         │
        │ u32    ┆ str          ┆ str         │
        ╞════════╪══════════════╪═════════════╡
        │ 0      ┆ FR           ┆ France      │
        │ 1      ┆ ES           ┆ 1           │
        │ 2      ┆ DE           ┆ Germany     │
        │ 3      ┆ null         ┆ unspecified │
        └────────┴──────────────┴─────────────┘
        """

        def _remap_key_or_value_series(
            name: str,
            values: Iterable[Any],
            dtype: PolarsDataType | None,
            dtype_if_empty: PolarsDataType | None,
            dtype_keys: PolarsDataType | None,
            *,
            is_keys: bool,
        ) -> Series:
            """
            Convert mapping keys or mapping values to `Series` with `dtype`.

            Try to convert the mapping keys or mapping values to `Series` with
            the specified dtype and check that none of the values are accidentally
            lost (replaced by nulls) during the conversion.

            Parameters
            ----------
            name
                Name of the keys or values Series.
            values
                Values for the Series: `mapping.keys()` or `mapping.values()`.
            dtype
                User specified dtype. If None,
            dtype_if_empty
                If no dtype is specified and values contains None, an empty list,
                or a list with only None values, set the Polars dtype of the Series
                data.
            dtype_keys
                If user set dtype is None, try to see if Series for mapping.values()
                can be converted to same dtype as the mapping.keys() Series dtype.
            is_keys
                If values contains keys or values from mapping dict.

            """
            try:
                if dtype is None:
                    # If no dtype was set, which should only happen when:
                    #     values = mapping.values()
                    # create a Series from those values and infer the dtype.
                    s = pl.Series(
                        name,
                        values,
                        dtype=None,
                        dtype_if_empty=dtype_if_empty,
                        strict=True,
                    )

                    if dtype_keys is not None:
                        if s.dtype == dtype_keys:
                            # Values Series has same dtype as keys Series.
                            dtype = s.dtype
                        elif (
                            (s.dtype.is_integer() and dtype_keys.is_integer())
                            or (s.dtype.is_float() and dtype_keys.is_float())
                            or (s.dtype == Utf8 and dtype_keys == Categorical)
                        ):
                            # Values Series and keys Series are of similar dtypes,
                            # that we can assume that the user wants the values Series
                            # of the same dtype as the key Series.
                            dtype = dtype_keys
                            s = pl.Series(
                                name,
                                values,
                                dtype=dtype_keys,
                                dtype_if_empty=dtype_if_empty,
                                strict=True,
                            )
                            if dtype != s.dtype:
                                raise ValueError(
                                    f"mapping values for `replace` could not be converted to {dtype!r}: found {s.dtype!r}"
                                )
                else:
                    # dtype was set, which should always be the case when:
                    #     values = mapping.keys()
                    # and in cases where the user set the output dtype when:
                    #     values = mapping.values()
                    s = pl.Series(
                        name,
                        values,
                        dtype=dtype,
                        dtype_if_empty=dtype_if_empty,
                        strict=True,
                    )
                    if dtype != s.dtype:
                        raise ValueError(
                            f"mapping {'keys' if is_keys else 'values'} for `replace` could not be converted to {dtype!r}: found {s.dtype!r}"
                        )

            except OverflowError as exc:
                if is_keys:
                    raise ValueError(
                        f"mapping keys for `replace` could not be converted to {dtype!r}: {exc!s}"
                    ) from exc
                else:
                    raise ValueError(
                        f"choose a more suitable output dtype for `replace` as mapping value could not be converted to {dtype!r}: {exc!s}"
                    ) from exc

            if is_keys:
                # values = mapping.keys()
                if s.null_count() == 0:  # noqa: SIM114
                    pass
                elif s.null_count() == 1 and None in mapping:
                    pass
                else:
                    raise ValueError(
                        f"mapping keys for `replace` could not be converted to {dtype!r} without losing values in the conversion"
                    )
            else:
                # values = mapping.values()
                if s.null_count() == 0:  # noqa: SIM114
                    pass
                elif s.len() - s.null_count() == len(list(filter(None, values))):
                    pass
                else:
                    raise ValueError(
                        f"remapping values for `replace` could not be converted to {dtype!r} without losing values in the conversion"
                    )
            return s

        def inner_func(s: Series, default_value: Any = None) -> Series:
            # Convert Series to:
            #   - multicolumn DataFrame, if Series is a Struct.
            #   - one column DataFrame in other cases.
            df = s.to_frame().unnest(s.name) if s.dtype == Struct else s.to_frame()

            # For struct we always apply mapping to the first column.
            column = df.columns[0]
            input_dtype = df.dtypes[0]
            remap_key_column = f"__POLARS_REMAP_KEY_{column}"
            remap_value_column = f"__POLARS_REMAP_VALUE_{column}"
            is_remapped_column = f"__POLARS_REMAP_IS_REMAPPED_{column}"

            # Set output dtype:
            #  - to dtype, if specified.
            #  - to same dtype as expression specified as default value.
            #  - to None, if dtype was not specified and default was not an expression.
            return_dtype_ = (
                df.lazy().select(default).dtypes[0]
                if return_dtype is None and isinstance(default, Expr)
                else return_dtype
            )
            remap_key_s = _remap_key_or_value_series(
                name=remap_key_column,
                values=mapping.keys(),
                dtype=input_dtype,
                dtype_if_empty=input_dtype,
                dtype_keys=input_dtype,
                is_keys=True,
            )
            if return_dtype_:
                # Create remap value Series with specified output dtype.
                remap_value_s = pl.Series(
                    remap_value_column,
                    mapping.values(),
                    dtype=return_dtype_,
                    dtype_if_empty=input_dtype,
                )
            else:
                # Create remap value Series with same output dtype as remap key Series,
                # if possible (if both are integers, both are floats or remap value
                # Series is pl.Utf8 and remap key Series is pl.Categorical).
                remap_value_s = _remap_key_or_value_series(
                    name=remap_value_column,
                    values=mapping.values(),
                    dtype=None,
                    dtype_if_empty=input_dtype,
                    dtype_keys=input_dtype,
                    is_keys=False,
                )

            remap_frame = pl.LazyFrame(data=[remap_key_s, remap_value_s]).with_columns(
                F.lit(True).alias(is_remapped_column)
            )
            mapped = df.lazy().join(
                other=remap_frame, how="left", left_on=column, right_on=remap_key_column
            )
            if default_value is None:
                result_index = 1
            else:
                expr_default = parse_as_expression(default_value, str_as_lit=True)
                default_parsed = self._from_pyexpr(expr_default)
                mapped = mapped.select(
                    F.when(F.col(is_remapped_column).is_not_null())
                    .then(F.col(remap_value_column))
                    .otherwise(default_parsed)
                    .alias(column)
                )
                result_index = 0

            return mapped.collect(no_optimization=True).to_series(index=result_index)

        if default is no_default:
            default = F.first()

        mapping_func = partial(inner_func, default_value=default)
        return self.map_batches(function=mapping_func, return_dtype=return_dtype)

    @deprecate_renamed_function("map_batches", version="0.19.0")
    def map(
        self,
        function: Callable[[Series], Series | Any],
        return_dtype: PolarsDataType | None = None,
        *,
        agg_list: bool = False,
    ) -> Self:
        """
        Apply a custom python function to a Series or sequence of Series.

        .. deprecated:: 0.19.0
            This method has been renamed to :func:`Expr.map_batches`.

        Parameters
        ----------
        function
            Lambda/ function to apply.
        return_dtype
            Dtype of the output Series.
        agg_list
            Aggregate list

        """
        return self.map_batches(function, return_dtype, agg_list=agg_list)

    @deprecate_renamed_function("map_elements", version="0.19.0")
    def apply(
        self,
        function: Callable[[Series], Series] | Callable[[Any], Any],
        return_dtype: PolarsDataType | None = None,
        *,
        skip_nulls: bool = True,
        pass_name: bool = False,
        strategy: MapElementsStrategy = "thread_local",
    ) -> Self:
        """
        Apply a custom/user-defined function (UDF) in a GroupBy or Projection context.

        .. deprecated:: 0.19.0
            This method has been renamed to :func:`Expr.map_elements`.

        Parameters
        ----------
        function
            Lambda/ function to apply.
        return_dtype
            Dtype of the output Series.
            If not set, the dtype will be
            `polars.Unknown`.
        skip_nulls
            Don't apply the function over values
            that contain nulls. This is faster.
        pass_name
            Pass the Series name to the custom function
            This is more expensive.
        strategy : {'thread_local', 'threading'}
            This functionality is in `alpha` stage. This may be removed
            /changed without it being considered a breaking change.

            - 'thread_local': run the python function on a single thread.
            - 'threading': run the python function on separate threads. Use with
                        care as this can slow performance. This might only speed up
                        your code if the amount of work per element is significant
                        and the python function releases the GIL (e.g. via calling
                        a c function)

        """
        return self.map_elements(
            function,
            return_dtype=return_dtype,
            skip_nulls=skip_nulls,
            pass_name=pass_name,
            strategy=strategy,
        )

    @deprecate_renamed_function("rolling_map", version="0.19.0")
    def rolling_apply(
        self,
        function: Callable[[Series], Any],
        window_size: int,
        weights: list[float] | None = None,
        min_periods: int | None = None,
        *,
        center: bool = False,
    ) -> Self:
        """
        Apply a custom rolling window function.

        .. deprecated:: 0.19.0
            This method has been renamed to :func:`Expr.rolling_map`.

        Parameters
        ----------
        function
            Aggregation function
        window_size
            The length of the window.
        weights
            An optional slice with the same length as the window that will be multiplied
            elementwise with the values in the window.
        min_periods
            The number of values in the window that should be non-null before computing
            a result. If None, it will be set equal to window size.
        center
            Set the labels at the center of the window

        """
        return self.rolling_map(
            function, window_size, weights, min_periods, center=center
        )

    @deprecate_renamed_function("is_first_distinct", version="0.19.3")
    def is_first(self) -> Self:
        """
        Return a boolean mask indicating the first occurrence of each distinct value.

        .. deprecated:: 0.19.3
            This method has been renamed to :func:`Expr.is_first_distinct`.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        """
        return self.is_first_distinct()

    @deprecate_renamed_function("is_last_distinct", version="0.19.3")
    def is_last(self) -> Self:
        """
        Return a boolean mask indicating the last occurrence of each distinct value.

        .. deprecated:: 0.19.3
            This method has been renamed to :func:`Expr.is_last_distinct`.

        Returns
        -------
        Expr
            Expression of data type :class:`Boolean`.

        """
        return self.is_last_distinct()

    @deprecate_function("Use `clip` instead.", version="0.19.12")
    def clip_min(
        self, lower_bound: NumericLiteral | TemporalLiteral | IntoExprColumn
    ) -> Self:
        """
        Clip (limit) the values in an array to a `min` boundary.

        .. deprecated:: 0.19.12
            Use :func:`clip` instead.

        Parameters
        ----------
        lower_bound
            Lower bound.

        """
        return self.clip(lower_bound=lower_bound)

    @deprecate_function("Use `clip` instead.", version="0.19.12")
    def clip_max(
        self, upper_bound: NumericLiteral | TemporalLiteral | IntoExprColumn
    ) -> Self:
        """
        Clip (limit) the values in an array to a `max` boundary.

        .. deprecated:: 0.19.12
            Use :func:`clip` instead.

        Parameters
        ----------
        upper_bound
            Upper bound.

        """
        return self.clip(upper_bound=upper_bound)

    @deprecate_function("Use `shift` instead.", version="0.19.12")
    @deprecate_renamed_parameter("periods", "n", version="0.19.11")
    def shift_and_fill(
        self,
        fill_value: IntoExpr,
        *,
        n: int = 1,
    ) -> Self:
        """
        Shift values by the given number of places and fill the resulting null values.

        .. deprecated:: 0.19.12
            Use :func:`shift` instead.

        Parameters
        ----------
        fill_value
            Fill None values with the result of this expression.
        n
            Number of places to shift (may be negative).

        """
        return self.shift(n, fill_value=fill_value)

    def register_plugin(
        self,
        *,
        lib: str,
        symbol: str,
        args: list[IntoExpr] | None = None,
        kwargs: dict[Any, Any] | None = None,
        is_elementwise: bool = False,
        input_wildcard_expansion: bool = False,
        returns_scalar: bool = False,
        cast_to_supertypes: bool = False,
        pass_name_to_apply: bool = False,
        changes_length: bool = False,
    ) -> Self:
        """
        Register a shared library as a plugin.

        .. warning::
            This is highly unsafe as this will call the C function
            loaded by `lib::symbol`.

            The parameters you give dictate how polars will deal
            with the function. Make sure they are correct!

        .. note::
            This functionality is unstable and may change without it
            being considered breaking.

        Parameters
        ----------
        lib
            Library to load.
        symbol
            Function to load.
        args
            Arguments (other than self) passed to this function.
            These arguments have to be of type Expression.
        kwargs
            Non-expression arguments. They must be JSON serializable.
        is_elementwise
            If the function only operates on scalars
            this will trigger fast paths.
        input_wildcard_expansion
            Expand expressions as input of this function.
        returns_scalar
            Automatically explode on unit length if it ran as final aggregation.
            this is the case for aggregations like `sum`, `min`, `covariance` etc.
        cast_to_supertypes
            Cast the input datatypes to their supertype.
        pass_name_to_apply
            if set, then the `Series` passed to the function in the group_by operation
            will ensure the name is set. This is an extra heap allocation per group.
        changes_length
            For example a `unique` or a `slice`

        """
        if args is None:
            args = []
        else:
            args = [parse_as_expression(a) for a in args]
        if kwargs is None:
            serialized_kwargs = b""
        else:
            import pickle

            # Choose the highest protocol supported by https://docs.rs/serde-pickle/latest/serde_pickle/
            serialized_kwargs = pickle.dumps(kwargs, protocol=5)

        return self._from_pyexpr(
            self._pyexpr.register_plugin(
                lib,
                symbol,
                args,
                serialized_kwargs,
                is_elementwise,
                input_wildcard_expansion,
                returns_scalar,
                cast_to_supertypes,
                pass_name_to_apply,
                changes_length,
            )
        )

    @deprecate_renamed_function("register_plugin", version="0.19.12")
    def _register_plugin(
        self,
        *,
        lib: str,
        symbol: str,
        args: list[IntoExpr] | None = None,
        kwargs: dict[Any, Any] | None = None,
        is_elementwise: bool = False,
        input_wildcard_expansion: bool = False,
        auto_explode: bool = False,
        cast_to_supertypes: bool = False,
    ) -> Self:
        return self.register_plugin(
            lib=lib,
            symbol=symbol,
            args=args,
            kwargs=kwargs,
            is_elementwise=is_elementwise,
            input_wildcard_expansion=input_wildcard_expansion,
            returns_scalar=auto_explode,
            cast_to_supertypes=cast_to_supertypes,
        )

    @deprecate_renamed_function("gather_every", version="0.19.14")
    def take_every(self, n: int) -> Self:
        """
        Take every nth value in the Series and return as a new Series.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`gather_every`.

        Parameters
        ----------
        n
            Gather every *n*-th row.
        """
        return self.gather_every(n)

    @deprecate_renamed_function("gather", version="0.19.14")
    def take(
        self, indices: int | list[int] | Expr | Series | np.ndarray[Any, Any]
    ) -> Self:
        """
        Take values by index.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`gather`.

        Parameters
        ----------
        indices
            An expression that leads to a UInt32 dtyped Series.
        """
        return self.gather(indices)

    @deprecate_renamed_function("cum_sum", version="0.19.14")
    def cumsum(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative sum computed at every element.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`cum_sum`.

        Parameters
        ----------
        reverse
            Reverse the operation.
        """
        return self.cum_sum(reverse=reverse)

    @deprecate_renamed_function("cum_prod", version="0.19.14")
    def cumprod(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative product computed at every element.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`cum_prod`.

        Parameters
        ----------
        reverse
            Reverse the operation.
        """
        return self.cum_prod(reverse=reverse)

    @deprecate_renamed_function("cum_min", version="0.19.14")
    def cummin(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative min computed at every element.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`cum_min`.

        Parameters
        ----------
        reverse
            Reverse the operation.
        """
        return self.cum_min(reverse=reverse)

    @deprecate_renamed_function("cum_max", version="0.19.14")
    def cummax(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative max computed at every element.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`cum_max`.

        Parameters
        ----------
        reverse
            Reverse the operation.
        """
        return self.cum_max(reverse=reverse)

    @deprecate_renamed_function("cum_count", version="0.19.14")
    def cumcount(self, *, reverse: bool = False) -> Self:
        """
        Get an array with the cumulative count computed at every element.

        .. deprecated:: 0.19.14
            This method has been renamed to :meth:`cum_count`.

        Parameters
        ----------
        reverse
            Reverse the operation.
        """
        return self.cum_count(reverse=reverse)

    @deprecate_function(
        "It has been renamed to `replace`."
        " The default behavior has changed to keep any values not present in the mapping unchanged."
        " Pass `default=None` to keep existing behavior.",
        version="0.19.16",
    )
    @deprecate_renamed_parameter("remapping", "mapping", version="0.19.16")
    def map_dict(
        self,
        mapping: dict[Any, Any],
        *,
        default: Any = None,
        return_dtype: PolarsDataType | None = None,
    ) -> Self:
        """
        Replace values in column according to remapping dictionary.

        .. deprecated:: 0.19.16
            This method has been renamed to :meth:`replace`. The default behavior
            has changed to keep any values not present in the mapping unchanged.
            Pass `default=None` to keep existing behavior.

        Parameters
        ----------
        mapping
            Dictionary containing the before/after values to map.
        default
            Value to use when the remapping dict does not contain the lookup value.
            Accepts expression input. Non-expression inputs are parsed as literals.
            Use `pl.first()`, to keep the original value.
        return_dtype
            Set return dtype to override automatic return dtype determination.

        """
        return self.replace(mapping, default=default, return_dtype=return_dtype)

    @property
    def bin(self) -> ExprBinaryNameSpace:
        """
        Create an object namespace of all binary related methods.

        See the individual method pages for full details
        """
        return ExprBinaryNameSpace(self)

    @property
    def cat(self) -> ExprCatNameSpace:
        """
        Create an object namespace of all categorical related methods.

        See the individual method pages for full details

        Examples
        --------
        >>> df = pl.DataFrame({"values": ["a", "b"]}).select(
        ...     pl.col("values").cast(pl.Categorical)
        ... )
        >>> df.select(pl.col("values").cat.set_ordering(ordering="physical"))
        shape: (2, 1)
        ┌────────┐
        │ values │
        │ ---    │
        │ cat    │
        ╞════════╡
        │ a      │
        │ b      │
        └────────┘

        """
        return ExprCatNameSpace(self)

    @property
    def dt(self) -> ExprDateTimeNameSpace:
        """Create an object namespace of all datetime related methods."""
        return ExprDateTimeNameSpace(self)

    # Keep the `list` and `str` properties below at the end of the definition of Expr,
    # as to not confuse mypy with the type annotation `str` and `list`

    @property
    def list(self) -> ExprListNameSpace:
        """
        Create an object namespace of all list related methods.

        See the individual method pages for full details.

        """
        return ExprListNameSpace(self)

    @property
    def arr(self) -> ExprArrayNameSpace:
        """
        Create an object namespace of all array related methods.

        See the individual method pages for full details.

        """
        return ExprArrayNameSpace(self)

    @property
    def meta(self) -> ExprMetaNameSpace:
        """
        Create an object namespace of all meta related expression methods.

        This can be used to modify and traverse existing expressions.

        """
        return ExprMetaNameSpace(self)

    @property
    def name(self) -> ExprNameNameSpace:
        """
        Create an object namespace of all expressions that modify expression names.

        See the individual method pages for full details.

        """
        return ExprNameNameSpace(self)

    @property
    def str(self) -> ExprStringNameSpace:
        """
        Create an object namespace of all string related methods.

        See the individual method pages for full details.

        Examples
        --------
        >>> df = pl.DataFrame({"letters": ["a", "b"]})
        >>> df.select(pl.col("letters").str.to_uppercase())
        shape: (2, 1)
        ┌─────────┐
        │ letters │
        │ ---     │
        │ str     │
        ╞═════════╡
        │ A       │
        │ B       │
        └─────────┘

        """
        return ExprStringNameSpace(self)

    @property
    def struct(self) -> ExprStructNameSpace:
        """
        Create an object namespace of all struct related methods.

        See the individual method pages for full details.

        Examples
        --------
        >>> df = (
        ...     pl.DataFrame(
        ...         {
        ...             "int": [1, 2],
        ...             "str": ["a", "b"],
        ...             "bool": [True, None],
        ...             "list": [[1, 2], [3]],
        ...         }
        ...     )
        ...     .to_struct("my_struct")
        ...     .to_frame()
        ... )
        >>> df.select(pl.col("my_struct").struct.field("str"))
        shape: (2, 1)
        ┌─────┐
        │ str │
        │ --- │
        │ str │
        ╞═════╡
        │ a   │
        │ b   │
        └─────┘

        """
        return ExprStructNameSpace(self)


def _prepare_alpha(
    com: float | int | None = None,
    span: float | int | None = None,
    half_life: float | int | None = None,
    alpha: float | int | None = None,
) -> float:
    """Normalise EWM decay specification in terms of smoothing factor 'alpha'."""
    if sum((param is not None) for param in (com, span, half_life, alpha)) > 1:
        raise ValueError(
            "parameters `com`, `span`, `half_life`, and `alpha` are mutually exclusive"
        )
    if com is not None:
        if com < 0.0:
            raise ValueError(f"require `com` >= 0 (found {com!r})")
        alpha = 1.0 / (1.0 + com)

    elif span is not None:
        if span < 1.0:
            raise ValueError(f"require `span` >= 1 (found {span!r})")
        alpha = 2.0 / (span + 1.0)

    elif half_life is not None:
        if half_life <= 0.0:
            raise ValueError(f"require `half_life` > 0 (found {half_life!r})")
        alpha = 1.0 - math.exp(-math.log(2.0) / half_life)

    elif alpha is None:
        raise ValueError("one of `com`, `span`, `half_life`, or `alpha` must be set")

    elif not (0 < alpha <= 1):
        raise ValueError(f"require 0 < `alpha` <= 1 (found {alpha!r})")

    return alpha


def _prepare_rolling_window_args(
    window_size: int | timedelta | str,
    min_periods: int | None = None,
) -> tuple[str, int]:
    if isinstance(window_size, int):
        if window_size < 1:
            raise ValueError("`window_size` must be positive")

        if min_periods is None:
            min_periods = window_size
        window_size = f"{window_size}i"
    elif isinstance(window_size, timedelta):
        window_size = _timedelta_to_pl_duration(window_size)
    if min_periods is None:
        min_periods = 1
    return window_size, min_periods