DEPR: keyword-only arguments for DataFrame/Series statistical methods

doc/source/user_guide/basics.rst

@@ -476,15 +476,15 @@ For example:
 .. ipython:: python
 
    df
-   df.mean(0)
-   df.mean(1)
+   df.mean(axis=0)
+   df.mean(axis=1)
 
 All such methods have a ``skipna`` option signaling whether to exclude missing
 data (``True`` by default):
 
 .. ipython:: python
 
-   df.sum(0, skipna=False)
+   df.sum(axis=0, skipna=False)
    df.sum(axis=1, skipna=True)
 
 Combined with the broadcasting / arithmetic behavior, one can describe various
@@ -495,8 +495,8 @@ standard deviation of 1), very concisely:
 
    ts_stand = (df - df.mean()) / df.std()
    ts_stand.std()
-   xs_stand = df.sub(df.mean(1), axis=0).div(df.std(1), axis=0)
-   xs_stand.std(1)
+   xs_stand = df.sub(df.mean(axis=1), axis=0).div(df.std(axis=1), axis=0)
+   xs_stand.std(axis=1)
 
 Note that methods like :meth:`~DataFrame.cumsum` and :meth:`~DataFrame.cumprod`
 preserve the location of ``NaN`` values. This is somewhat different from

doc/source/user_guide/indexing.rst

@@ -952,7 +952,7 @@ To select a row where each column meets its own criterion:
 
   values = {'ids': ['a', 'b'], 'ids2': ['a', 'c'], 'vals': [1, 3]}
 
-  row_mask = df.isin(values).all(1)
+  row_mask = df.isin(values).all(axis=1)
 
   df[row_mask]
 

doc/source/whatsnew/v3.0.0.rst

@@ -190,6 +190,7 @@ Other Deprecations
 
 - Deprecated :meth:`Timestamp.utcfromtimestamp`, use ``Timestamp.fromtimestamp(ts, "UTC")`` instead (:issue:`56680`)
 - Deprecated :meth:`Timestamp.utcnow`, use ``Timestamp.now("UTC")`` instead (:issue:`56680`)
+- Deprecated allowing non-keyword arguments in :meth:`DataFrame.all`, :meth:`DataFrame.min`, :meth:`DataFrame.max`, :meth:`DataFrame.sum`, :meth:`DataFrame.prod`, :meth:`DataFrame.mean`, :meth:`DataFrame.median`, :meth:`DataFrame.sem`, :meth:`DataFrame.var`, :meth:`DataFrame.std`, :meth:`DataFrame.skew`, :meth:`DataFrame.kurt`, :meth:`Series.all`,  :meth:`Series.min`, :meth:`Series.max`, :meth:`Series.sum`, :meth:`Series.prod`, :meth:`Series.mean`, :meth:`Series.median`, :meth:`Series.sem`, :meth:`Series.var`, :meth:`Series.std`, :meth:`Series.skew`, and :meth:`Series.kurt`. (:issue:`57087`)
 - Deprecated allowing non-keyword arguments in :meth:`Series.to_markdown` except ``buf``. (:issue:`57280`)
 - Deprecated allowing non-keyword arguments in :meth:`Series.to_string` except ``buf``. (:issue:`57280`)
 -

pandas/core/frame.py

@@ -64,6 +64,7 @@
 from pandas.util._decorators import (
     Appender,
     Substitution,
+    deprecate_nonkeyword_arguments,
     doc,
     set_module,
 )
@@ -11543,6 +11544,7 @@ def all(
         **kwargs,
     ) -> Series | bool: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="all")
     @doc(make_doc("all", ndim=1))
     def all(
         self,
@@ -11589,6 +11591,7 @@ def min(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="min")
     @doc(make_doc("min", ndim=2))
     def min(
         self,
@@ -11635,6 +11638,7 @@ def max(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="max")
     @doc(make_doc("max", ndim=2))
     def max(
         self,
@@ -11650,6 +11654,7 @@ def max(
             result = result.__finalize__(self, method="max")
         return result
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="sum")
     @doc(make_doc("sum", ndim=2))
     def sum(
         self,
@@ -11670,6 +11675,7 @@ def sum(
             result = result.__finalize__(self, method="sum")
         return result
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="prod")
     @doc(make_doc("prod", ndim=2))
     def prod(
         self,
@@ -11721,6 +11727,7 @@ def mean(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="mean")
     @doc(make_doc("mean", ndim=2))
     def mean(
         self,
@@ -11767,6 +11774,7 @@ def median(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="median")
     @doc(make_doc("median", ndim=2))
     def median(
         self,
@@ -11816,6 +11824,7 @@ def sem(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="sem")
     @doc(make_doc("sem", ndim=2))
     def sem(
         self,
@@ -11866,6 +11875,7 @@ def var(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="var")
     @doc(make_doc("var", ndim=2))
     def var(
         self,
@@ -11916,6 +11926,7 @@ def std(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="std")
     @doc(make_doc("std", ndim=2))
     def std(
         self,
@@ -11963,6 +11974,7 @@ def skew(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="skew")
     @doc(make_doc("skew", ndim=2))
     def skew(
         self,
@@ -12009,6 +12021,7 @@ def kurt(
         **kwargs,
     ) -> Series | Any: ...
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="kurt")
     @doc(make_doc("kurt", ndim=2))
     def kurt(
         self,

pandas/core/series.py

@@ -6189,6 +6189,7 @@ def any(  # type: ignore[override]
             filter_type="bool",
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="all")
     @Appender(make_doc("all", ndim=1))
     def all(
         self,
@@ -6208,6 +6209,7 @@ def all(
             filter_type="bool",
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="min")
     @doc(make_doc("min", ndim=1))
     def min(
         self,
@@ -6220,6 +6222,7 @@ def min(
             self, axis=axis, skipna=skipna, numeric_only=numeric_only, **kwargs
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="max")
     @doc(make_doc("max", ndim=1))
     def max(
         self,
@@ -6232,6 +6235,7 @@ def max(
             self, axis=axis, skipna=skipna, numeric_only=numeric_only, **kwargs
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="sum")
     @doc(make_doc("sum", ndim=1))
     def sum(
         self,
@@ -6250,6 +6254,7 @@ def sum(
             **kwargs,
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="prod")
     @doc(make_doc("prod", ndim=1))
     def prod(
         self,
@@ -6268,6 +6273,7 @@ def prod(
             **kwargs,
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="mean")
     @doc(make_doc("mean", ndim=1))
     def mean(
         self,
@@ -6280,6 +6286,7 @@ def mean(
             self, axis=axis, skipna=skipna, numeric_only=numeric_only, **kwargs
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="median")
     @doc(make_doc("median", ndim=1))
     def median(
         self,
@@ -6292,6 +6299,7 @@ def median(
             self, axis=axis, skipna=skipna, numeric_only=numeric_only, **kwargs
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="sem")
     @doc(make_doc("sem", ndim=1))
     def sem(
         self,
@@ -6310,6 +6318,7 @@ def sem(
             **kwargs,
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="var")
     @doc(make_doc("var", ndim=1))
     def var(
         self,
@@ -6328,6 +6337,7 @@ def var(
             **kwargs,
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="std")
     @doc(make_doc("std", ndim=1))
     def std(
         self,
@@ -6346,6 +6356,7 @@ def std(
             **kwargs,
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="skew")
     @doc(make_doc("skew", ndim=1))
     def skew(
         self,
@@ -6358,6 +6369,7 @@ def skew(
             self, axis=axis, skipna=skipna, numeric_only=numeric_only, **kwargs
         )
 
+    @deprecate_nonkeyword_arguments(version="3.0", allowed_args=["self"], name="kurt")
     @doc(make_doc("kurt", ndim=1))
     def kurt(
         self,

pandas/tests/apply/test_frame_apply.py

@@ -402,7 +402,7 @@ def test_apply_yield_list(float_frame):
 
 def test_apply_reduce_Series(float_frame):
     float_frame.iloc[::2, float_frame.columns.get_loc("A")] = np.nan
-    expected = float_frame.mean(1)
+    expected = float_frame.mean(axis=1)
     result = float_frame.apply(np.mean, axis=1)
     tm.assert_series_equal(result, expected)
 

pandas/tests/apply/test_str.py

@@ -19,27 +19,18 @@
 
 @pytest.mark.parametrize("func", ["sum", "mean", "min", "max", "std"])
 @pytest.mark.parametrize(
-    "args,kwds",
+    "kwds",
     [
-        pytest.param([], {}, id="no_args_or_kwds"),
-        pytest.param([1], {}, id="axis_from_args"),
-        pytest.param([], {"axis": 1}, id="axis_from_kwds"),
-        pytest.param([], {"numeric_only": True}, id="optional_kwds"),
-        pytest.param([1, True], {"numeric_only": True}, id="args_and_kwds"),
+        pytest.param({}, id="no_kwds"),
+        pytest.param({"axis": 1}, id="on_axis"),
+        pytest.param({"numeric_only": True}, id="func_kwds"),
+        pytest.param({"axis": 1, "numeric_only": True}, id="axis_and_func_kwds"),
     ],
 )
 @pytest.mark.parametrize("how", ["agg", "apply"])
-def test_apply_with_string_funcs(request, float_frame, func, args, kwds, how):
-    if len(args) > 1 and how == "agg":
-        request.applymarker(
-            pytest.mark.xfail(
-                raises=TypeError,
-                reason="agg/apply signature mismatch - agg passes 2nd "
-                "argument to func",
-            )
-        )
-    result = getattr(float_frame, how)(func, *args, **kwds)
-    expected = getattr(float_frame, func)(*args, **kwds)
+def test_apply_with_string_funcs(request, float_frame, func, kwds, how):
+    result = getattr(float_frame, how)(func, **kwds)
+    expected = getattr(float_frame, func)(**kwds)
     tm.assert_series_equal(result, expected)
 
 

pandas/tests/frame/methods/test_asof.py

@@ -36,18 +36,18 @@ def test_basic(self, date_range_frame):
         dates = date_range("1/1/1990", periods=N * 3, freq="25s")
 
         result = df.asof(dates)
-        assert result.notna().all(1).all()
+        assert result.notna().all(axis=1).all()
         lb = df.index[14]
         ub = df.index[30]
 
         dates = list(dates)
 
         result = df.asof(dates)
-        assert result.notna().all(1).all()
+        assert result.notna().all(axis=1).all()
 
         mask = (result.index >= lb) & (result.index < ub)
         rs = result[mask]
-        assert (rs == 14).all(1).all()
+        assert (rs == 14).all(axis=1).all()
 
     def test_subset(self, date_range_frame):
         N = 10

pandas/tests/frame/methods/test_fillna.py

@@ -466,7 +466,7 @@ def test_fillna_dict_series(self):
 
         # disable this for now
         with pytest.raises(NotImplementedError, match="column by column"):
-            df.fillna(df.max(1), axis=1)
+            df.fillna(df.max(axis=1), axis=1)
 
     def test_fillna_dataframe(self):
         # GH#8377

pandas/tests/frame/test_reductions.py

@@ -773,7 +773,7 @@ def test_operators_timedelta64(self):
         tm.assert_series_equal(result, expected)
 
         # works when only those columns are selected
-        result = mixed[["A", "B"]].min(1)
+        result = mixed[["A", "B"]].min(axis=1)
         expected = Series([timedelta(days=-1)] * 3)
         tm.assert_series_equal(result, expected)
 
@@ -832,8 +832,8 @@ def test_std_datetime64_with_nat(self, values, skipna, request, unit):
     def test_sum_corner(self):
         empty_frame = DataFrame()
 
-        axis0 = empty_frame.sum(0)
-        axis1 = empty_frame.sum(1)
+        axis0 = empty_frame.sum(axis=0)
+        axis1 = empty_frame.sum(axis=1)
         assert isinstance(axis0, Series)
         assert isinstance(axis1, Series)
         assert len(axis0) == 0
@@ -967,8 +967,8 @@ def test_sum_object(self, float_frame):
     def test_sum_bool(self, float_frame):
         # ensure this works, bug report
         bools = np.isnan(float_frame)
-        bools.sum(1)
-        bools.sum(0)
+        bools.sum(axis=1)
+        bools.sum(axis=0)
 
     def test_sum_mixed_datetime(self):
         # GH#30886
@@ -990,7 +990,7 @@ def test_mean_corner(self, float_frame, float_string_frame):
 
         # take mean of boolean column
         float_frame["bool"] = float_frame["A"] > 0
-        means = float_frame.mean(0)
+        means = float_frame.mean(axis=0)
         assert means["bool"] == float_frame["bool"].values.mean()
 
     def test_mean_datetimelike(self):
@@ -1043,13 +1043,13 @@ def test_mean_extensionarray_numeric_only_true(self):
 
     def test_stats_mixed_type(self, float_string_frame):
         with pytest.raises(TypeError, match="could not convert"):
-            float_string_frame.std(1)
+            float_string_frame.std(axis=1)
         with pytest.raises(TypeError, match="could not convert"):
-            float_string_frame.var(1)
+            float_string_frame.var(axis=1)
         with pytest.raises(TypeError, match="unsupported operand type"):
-            float_string_frame.mean(1)
+            float_string_frame.mean(axis=1)
         with pytest.raises(TypeError, match="could not convert"):
-            float_string_frame.skew(1)
+            float_string_frame.skew(axis=1)
 
     def test_sum_bools(self):
         df = DataFrame(index=range(1), columns=range(10))
@@ -1331,11 +1331,11 @@ def test_any_all_extra(self):
         result = df[["A", "B"]].any(axis=1, bool_only=True)
         tm.assert_series_equal(result, expected)
 
-        result = df.all(1)
+        result = df.all(axis=1)
         expected = Series([True, False, False], index=["a", "b", "c"])
         tm.assert_series_equal(result, expected)
 
-        result = df.all(1, bool_only=True)
+        result = df.all(axis=1, bool_only=True)
         tm.assert_series_equal(result, expected)
 
         # Axis is None