feat: pivot_table supports fill_value arg (#2257)

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Fixes #<issue_number_goes_here> 🦕

Author: TrevorBergeron

bigframes/core/reshape/pivot.py

@@ -71,12 +71,11 @@ def crosstab(
 columns=tmp_col_names,
 aggfunc=aggfuncor"count",
 sort=False,
+fill_value=0if (aggfuncisNone) elseNone,
  )
+# Undo temporary unique level labels
 pivot_table.index.names=rownamesor [i.nameforiinindex]
 pivot_table.columns.names=colnamesor [c.nameforcincolumns]
-ifaggfuncisNone:
-# TODO: Push this into pivot_table itself
-pivot_table=pivot_table.fillna(0)
 returnpivot_table
 
 

bigframes/dataframe.py

@@ -3486,10 +3486,6 @@ def pivot_table(
 observed: bool=False,
 sort: bool=True,
  ) ->DataFrame:
-iffill_valueisnotNone:
-raiseNotImplementedError(
-"DataFrame.pivot_table fill_value arg not supported. {constants.FEEDBACK_LINK}"
- )
 ifmargins:
 raiseNotImplementedError(
 "DataFrame.pivot_table margins arg not supported. {constants.FEEDBACK_LINK}"
@@ -3549,14 +3545,16 @@ def pivot_table(
 index=index,
 values=valuesiflen(values) >1elseNone,
  )
+iffill_valueisnotNone:
+pivoted=pivoted.fillna(fill_value)
 ifsort:
 pivoted=pivoted.sort_index()
 
 # TODO: Remove the reordering step once the issue is resolved.
 # The pivot_table method results in multi-index columns that are always ordered.
 # However, the order of the pivoted result columns is not guaranteed to be sorted.
 # Sort and reorder.
-returnpivoted[pivoted.columns.sort_values()]
+returnpivoted.sort_index(axis=1) # type: ignore
 
 defstack(self, level: LevelsType=-1):
 ifnotisinstance(self.columns, pandas.MultiIndex):

tests/system/small/test_dataframe.py

@@ -3784,12 +3784,18 @@ def test_df_pivot_hockey(hockey_df, hockey_pandas_df, values, index, columns):
 
 
 @pytest.mark.parametrize(
- ("values", "index", "columns", "aggfunc"),
+ ("values", "index", "columns", "aggfunc", "fill_value"),
  [
- (("culmen_length_mm", "body_mass_g"), "species", "sex", "std"),
- (["body_mass_g", "culmen_length_mm"], ("species", "island"), "sex", "sum"),
- ("body_mass_g", "sex", ["island", "species"], "mean"),
- ("culmen_depth_mm", "island", "species", "max"),
+ (("culmen_length_mm", "body_mass_g"), "species", "sex", "std", 1.0),
+ (
+ ["body_mass_g", "culmen_length_mm"],
+ ("species", "island"),
+"sex",
+"sum",
+None,
+ ),
+ ("body_mass_g", "sex", ["island", "species"], "mean", None),
+ ("culmen_depth_mm", "island", "species", "max", -1),
  ],
 )
 deftest_df_pivot_table(
@@ -3799,12 +3805,21 @@ def test_df_pivot_table(
 index,
 columns,
 aggfunc,
+fill_value,
 ):
 bf_result=penguins_df_default_index.pivot_table(
-values=values, index=index, columns=columns, aggfunc=aggfunc
+values=values,
+index=index,
+columns=columns,
+aggfunc=aggfunc,
+fill_value=fill_value,
  ).to_pandas()
 pd_result=penguins_pandas_df_default_index.pivot_table(
-values=values, index=index, columns=columns, aggfunc=aggfunc
+values=values,
+index=index,
+columns=columns,
+aggfunc=aggfunc,
+fill_value=fill_value,
  )
 pd.testing.assert_frame_equal(
 bf_result, pd_result, check_dtype=False, check_column_type=False

third_party/bigframes_vendored/pandas/core/frame.py

@@ -6414,6 +6414,10 @@ def pivot_table(self, values=None, index=None, columns=None, aggfunc="mean"):
  aggfunc (str, default "mean"):
  Aggregation function name to compute summary statistics (e.g., 'sum', 'mean').
 
+ fill_value (scalar, default None):
+ Value to replace missing values with (in the resulting pivot table, after
+ aggregation).
+
  Returns:
  bigframes.pandas.DataFrame: An Excel style pivot table.
  """