improve str -> date cast error message and fix wrong docstring (#1691)

pola-rs · Nov 7, 2021 · a230d36 · a230d36
1 parent 2c66829
commit a230d36
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Showing 2 changed files with 12 additions and 11 deletions.
diff --git a/polars/polars-core/src/series/mod.rs b/polars/polars-core/src/series/mod.rs
@@ -628,7 +628,8 @@ impl Series {
         if self.null_count() != s.null_count() {
             Err(PolarsError::ComputeError(
                 format!(
-                    "strict conversion of cast from {:?} to {:?} failed. consider non-strict cast.",
+                    "strict conversion of cast from {:?} to {:?} failed. consider non-strict cast.\n
+                    If you were trying to cast Utf8 to Date,Time,Datetime, consider using `strptime`",
                     self.dtype(),
                     data_type
                 )

diff --git a/py-polars/polars/eager/series.py b/py-polars/polars/eager/series.py
@@ -1655,21 +1655,21 @@ def cast(self, dtype: Type[DataType], strict: bool = True) -> "Series":
 
         Examples
         --------
-        >>> s = pl.Series("a", ["2020-01-01", "2020-01-02", "2020-01-03"])
+        >>> s = pl.Series("a", [True, False, True])
         shape: (3,)
-        Series: 'a' [str]
+        Series: 'a' [bool]
         [
-            "2020-01-01"
-            "2020-01-02"
-            "2020-01-03"
+            true
+            false
+            true
         ]
-        >>> s.cast(pl.datatypes.Date)
+        >>> s.cast(pl.UInt32)
         shape: (3,)
-        Series: 'a' [date]
+        Series: 'a' [u32]
         [
-            2020-01-01
-            2020-01-02
-            2020-01-03
+            1
+            0
+            1
         ]
 
         """