Some functions seem missing from the top level import

[aulemahal]

Describe the bug
It seems a few functions needed for the Array API are missing from the top level.

To Reproduce
Using xarray:

import numpy as np
import xarray as xr
from sparse import GCXS

x = np.random.negative_binomial(1, 0.5, size=(100, 100))
array = xr.DataArray(GCXS.from_numpy(x))
array.mean()

Fails with AttributeError: module 'sparse' has no attribute 'mean' on my machine.

I also had the problem with isnan on a float array.

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In[1], line 7
      5 x = np.random.negative_binomial(1, 0.5, size=(100, 100))
      6 array = xr.DataArray(GCXS.from_numpy(x))
----> 7 array.mean()

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/core/_aggregations.py:1663, in DataArrayAggregations.mean(self, dim, skipna, keep_attrs, **kwargs)
   1588 def mean(
   1589     self,
   1590     dim: Dims = None,
   (...)
   1594     **kwargs: Any,
   1595 ) -> Self:
   1596     """
   1597     Reduce this DataArray's data by applying ``mean`` along some dimension(s).
   1598 
   (...)
   1661     array(nan)
   1662     """
-> 1663     return self.reduce(
   1664         duck_array_ops.mean,
   1665         dim=dim,
   1666         skipna=skipna,
   1667         keep_attrs=keep_attrs,
   1668         **kwargs,
   1669     )

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/core/dataarray.py:3776, in DataArray.reduce(self, func, dim, axis, keep_attrs, keepdims, **kwargs)
   3732 def reduce(
   3733     self,
   3734     func: Callable[..., Any],
   (...)
   3740     **kwargs: Any,
   3741 ) -> Self:
   3742     """Reduce this array by applying `func` along some dimension(s).
   3743 
   3744     Parameters
   (...)
   3773         summarized data and the indicated dimension(s) removed.
   3774     """
-> 3776     var = self.variable.reduce(func, dim, axis, keep_attrs, keepdims, **kwargs)
   3777     return self._replace_maybe_drop_dims(var)

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/core/variable.py:1756, in Variable.reduce(self, func, dim, axis, keep_attrs, keepdims, **kwargs)
   1749 keep_attrs_ = (
   1750     _get_keep_attrs(default=False) if keep_attrs is None else keep_attrs
   1751 )
   1753 # Noe that the call order for Variable.mean is
   1754 #    Variable.mean -> NamedArray.mean -> Variable.reduce
   1755 #    -> NamedArray.reduce
-> 1756 result = super().reduce(
   1757     func=func, dim=dim, axis=axis, keepdims=keepdims, **kwargs
   1758 )
   1760 # return Variable always to support IndexVariable
   1761 return Variable(
   1762     result.dims, result._data, attrs=result._attrs if keep_attrs_ else None
   1763 )

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/namedarray/core.py:772, in NamedArray.reduce(self, func, dim, axis, keepdims, **kwargs)
    770         data = func(self.data, axis=axis, **kwargs)
    771     else:
--> 772         data = func(self.data, **kwargs)
    774 if getattr(data, "shape", ()) == self.shape:
    775     dims = self.dims

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/core/duck_array_ops.py:637, in mean(array, axis, skipna, **kwargs)
    635     return _to_pytimedelta(mean_timedeltas, unit="us") + offset
    636 else:
--> 637     return _mean(array, axis=axis, skipna=skipna, **kwargs)

File ~/mambaforge/envs/xesmf/lib/python3.11/site-packages/xarray/core/duck_array_ops.py:399, in _create_nan_agg_method.<locals>.f(values, axis, skipna, **kwargs)
    396         kwargs.pop("min_count", None)
    398     xp = get_array_namespace(values)
--> 399     func = getattr(xp, name)
    401 try:
    402     with warnings.catch_warnings():

AttributeError: module 'sparse' has no attribute 'mean'

Expected behavior
A mean to be computed.

System

• OS and version: Linux, Fedora 39
• sparse version : 0.15
• NumPy version : 1.26.3
• Numba version : 0.58.1

Additional context
This is an expanded copy of pydata/xarray#8602. I don't know much about the Array API, I am basing this issue on a comment on that other thread.

I only tested a few cases and had those problems:

• integer array and "mean"
• float array and "isnan"

integer arr

[hameerabbasi]

Thanks for the bug report, @aulemahal! This is indeed due to missing top level functions. I'll try to come up with a more complete list and make a PR.

[hameerabbasi]

PR is up at #623 if you'd like to test with your use-case.