from datetime import (
    date,
    timedelta,
)
from decimal import Decimal
import re

from dateutil.tz import tzlocal
import numpy as np
import pytest

from pandas.compat import (
    IS64,
    is_platform_windows,
)
from pandas.errors import Pandas4Warning
import pandas.util._test_decorators as td

import pandas as pd
import pandas._testing as tm
from pandas.core import (
    algorithms,
    nanops,
)
from pandas.tests.extension.decimal import DecimalArray

is_windows_np2_or_is32 = not IS64
is_windows_or_is32 = is_platform_windows() or not IS64


def _make_2d_ea_df(col_arrays, col_names):
    """
    Construct a DataFrame with a single 2D ExtensionArray block.

    Used for dt64tz and period types which support 2D blocks but don't
    consolidate automatically.
    """
    ea_type = type(col_arrays[0])
    ea_2d = ea_type._simple_new(
        np.stack([arr._ndarray for arr in col_arrays]),
        dtype=col_arrays[0].dtype,
    )
    return pd.DataFrame(ea_2d.T, columns=col_names)


def make_skipna_wrapper(alternative, skipna_alternative=None):
    """
    Create a function for calling on an array.

    Parameters
    ----------
    alternative : function
        The function to be called on the array with no NaNs.
        Only used when 'skipna_alternative' is None.
    skipna_alternative : function
        The function to be called on the original array

    Returns
    -------
    function
    """
    if skipna_alternative:

        def skipna_wrapper(x):
            return skipna_alternative(x.values)

    else:

        def skipna_wrapper(x):
            nona = x.dropna()
            if len(nona) == 0:
                return np.nan
            return alternative(nona)

    return skipna_wrapper


def assert_stat_op_calc(
    opname,
    alternative,
    frame,
    has_skipna=True,
    check_dtype=True,
    check_dates=False,
    rtol=1e-5,
    atol=1e-8,
    skipna_alternative=None,
):
    """
    Check that operator opname works as advertised on frame

    Parameters
    ----------
    opname : str
        Name of the operator to test on frame
    alternative : function
        Function that opname is tested against; i.e. "frame.opname()" should
        equal "alternative(frame)".
    frame : DataFrame
        The object that the tests are executed on
    has_skipna : bool, default True
        Whether the method "opname" has the kwarg "skipna"
    check_dtype : bool, default True
        Whether the dtypes of the result of "frame.opname()" and
        "alternative(frame)" should be checked.
    check_dates : bool, default false
        Whether opname should be tested on a Datetime Series
    rtol : float, default 1e-5
        Relative tolerance.
    atol : float, default 1e-8
        Absolute tolerance.
    skipna_alternative : function, default None
        NaN-safe version of alternative
    """
    f = getattr(frame, opname)

    if check_dates:
        df = pd.DataFrame({"b": pd.date_range("1/1/2001", periods=2)})
        with tm.assert_produces_warning(None):
            result = getattr(df, opname)()
        assert isinstance(result, pd.Series)

        df["a"] = range(len(df))
        with tm.assert_produces_warning(None):
            result = getattr(df, opname)()
        assert isinstance(result, pd.Series)
        assert len(result)

    if has_skipna:

        def wrapper(x):
            return alternative(x.values)

        skipna_wrapper = make_skipna_wrapper(alternative, skipna_alternative)
        result0 = f(axis=0, skipna=False)
        result1 = f(axis=1, skipna=False)
        tm.assert_series_equal(
            result0, frame.apply(wrapper), check_dtype=check_dtype, rtol=rtol, atol=atol
        )
        tm.assert_series_equal(
            result1,
            frame.apply(wrapper, axis=1),
            rtol=rtol,
            atol=atol,
        )
    else:
        skipna_wrapper = alternative

    result0 = f(axis=0)
    result1 = f(axis=1)
    tm.assert_series_equal(
        result0,
        frame.apply(skipna_wrapper),
        check_dtype=check_dtype,
        rtol=rtol,
        atol=atol,
    )

    if opname in ["sum", "prod"]:
        expected = frame.apply(skipna_wrapper, axis=1)
        tm.assert_series_equal(
            result1, expected, check_dtype=False, rtol=rtol, atol=atol
        )

    # check dtypes
    if check_dtype:
        lcd_dtype = frame.values.dtype
        assert lcd_dtype == result0.dtype
        assert lcd_dtype == result1.dtype

    # bad axis
    with pytest.raises(ValueError, match="No axis named 2"):
        f(axis=2)

    # all NA case
    if has_skipna:
        all_na = frame * np.nan
        r0 = getattr(all_na, opname)(axis=0)
        r1 = getattr(all_na, opname)(axis=1)
        if opname in ["sum", "prod"]:
            unit = 1 if opname == "prod" else 0  # result for empty sum/prod
            expected = pd.Series(unit, index=r0.index, dtype=r0.dtype)
            tm.assert_series_equal(r0, expected)
            expected = pd.Series(unit, index=r1.index, dtype=r1.dtype)
            tm.assert_series_equal(r1, expected)


@pytest.fixture
def bool_frame_with_na():
    """
    Fixture for DataFrame of booleans with index of unique strings

    Columns are ['A', 'B', 'C', 'D']; some entries are missing
    """
    df = pd.DataFrame(
        np.concatenate(
            [np.ones((15, 4), dtype=bool), np.zeros((15, 4), dtype=bool)], axis=0
        ),
        index=pd.Index([f"foo_{i}" for i in range(30)], dtype=object),
        columns=pd.Index(list("ABCD"), dtype=object),
        dtype=object,
    )
    # set some NAs
    df.iloc[5:10] = np.nan
    df.iloc[15:20, -2:] = np.nan
    return df


@pytest.fixture
def float_frame_with_na():
    """
    Fixture for DataFrame of floats with index of unique strings

    Columns are ['A', 'B', 'C', 'D']; some entries are missing
    """
    df = pd.DataFrame(
        np.random.default_rng(2).standard_normal((30, 4)),
        index=pd.Index([f"foo_{i}" for i in range(30)], dtype=object),
        columns=pd.Index(list("ABCD"), dtype=object),
    )
    # set some NAs
    df.iloc[5:10] = np.nan
    df.iloc[15:20, -2:] = np.nan
    return df


class TestDataFrameAnalytics:
    # ---------------------------------------------------------------------
    # Reductions
    @pytest.mark.parametrize("axis", [0, 1])
    @pytest.mark.parametrize(
        "opname",
        [
            "count",
            "sum",
            "mean",
            "product",
            "median",
            "min",
            "max",
            "nunique",
            "var",
            "std",
            "sem",
            pytest.param("skew", marks=td.skip_if_no("scipy")),
            pytest.param("kurt", marks=td.skip_if_no("scipy")),
        ],
    )
    def test_stat_op_api_float_string_frame(self, float_string_frame, axis, opname):
        if (opname in ("sum", "min", "max") and axis == 0) or opname in (
            "count",
            "nunique",
        ):
            getattr(float_string_frame, opname)(axis=axis)
        else:
            if opname in ["mean", "median", "var", "std", "sem", "skew", "kurt"]:
                # GH#66302 every statistic rejects the string column the same way
                msg = "Could not convert 'bar' to numeric"
            elif opname == "product":
                if axis == 1:
                    msg = "can't multiply sequence by non-int of type 'float'"
                else:
                    msg = "can't multiply sequence by non-int of type 'str'"
            elif opname == "sum":
                msg = r"unsupported operand type\(s\) for \+: 'float' and 'str'"
            elif opname in ["min", "max"]:
                msg = "'[><]=' not supported between instances of 'float' and 'str'"
            msg = "|".join([msg, "does not support", "Cannot perform reduction"])
            with pytest.raises(TypeError, match=msg):
                getattr(float_string_frame, opname)(axis=axis)
        if opname != "nunique":
            getattr(float_string_frame, opname)(axis=axis, numeric_only=True)

    @pytest.mark.parametrize("axis", [0, 1])
    @pytest.mark.parametrize(
        "opname",
        [
            "count",
            "sum",
            "mean",
            "product",
            "median",
            "min",
            "max",
            "var",
            "std",
            "sem",
            pytest.param("skew", marks=td.skip_if_no("scipy")),
            pytest.param("kurt", marks=td.skip_if_no("scipy")),
        ],
    )
    def test_stat_op_api_float_frame(self, float_frame, axis, opname):
        getattr(float_frame, opname)(axis=axis, numeric_only=False)

    def test_stat_op_calc(self, float_frame_with_na, mixed_float_frame):
        def count(s):
            return pd.notna(s).sum()

        def nunique(s):
            return len(algorithms.unique1d(s.dropna()))

        def var(x):
            return np.var(x, ddof=1)

        def std(x):
            return np.std(x, ddof=1)

        def sem(x):
            return np.std(x, ddof=1) / np.sqrt(len(x))

        assert_stat_op_calc(
            "nunique",
            nunique,
            float_frame_with_na,
            has_skipna=False,
            check_dtype=False,
            check_dates=True,
        )

        # GH#32571: rol needed for flaky CI builds
        # mixed types (with upcasting happening)
        assert_stat_op_calc(
            "sum",
            np.sum,
            mixed_float_frame.astype("float32"),
            check_dtype=False,
            rtol=1e-3,
        )

        assert_stat_op_calc(
            "sum", np.sum, float_frame_with_na, skipna_alternative=np.nansum
        )
        assert_stat_op_calc("mean", np.mean, float_frame_with_na, check_dates=True)
        assert_stat_op_calc(
            "product", np.prod, float_frame_with_na, skipna_alternative=np.nanprod
        )

        assert_stat_op_calc("var", var, float_frame_with_na)
        assert_stat_op_calc("std", std, float_frame_with_na)
        assert_stat_op_calc("sem", sem, float_frame_with_na)

        assert_stat_op_calc(
            "count",
            count,
            float_frame_with_na,
            has_skipna=False,
            check_dtype=False,
            check_dates=True,
        )

    def test_stat_op_calc_skew_kurtosis(self, float_frame_with_na):
        sp_stats = pytest.importorskip("scipy.stats")

        def skewness(x):
            if len(x) < 3:
                return np.nan
            return sp_stats.skew(x, bias=False)

        def kurt(x):
            if len(x) < 4:
                return np.nan
            return sp_stats.kurtosis(x, bias=False)

        assert_stat_op_calc("skew", skewness, float_frame_with_na)
        assert_stat_op_calc("kurt", kurt, float_frame_with_na)

    def test_median(self, float_frame_with_na, int_frame):
        def wrapper(x):
            if pd.isna(x).any():
                return np.nan
            return np.median(x)

        assert_stat_op_calc("median", wrapper, float_frame_with_na, check_dates=True)
        assert_stat_op_calc(
            "median", wrapper, int_frame, check_dtype=False, check_dates=True
        )

    @pytest.mark.parametrize(
        "method", ["sum", "mean", "prod", "var", "std", "skew", "min", "max"]
    )
    @pytest.mark.parametrize(
        "df",
        [
            pd.DataFrame(
                {
                    "a": [
                        -0.00049987540199591344,
                        -0.0016467257772919831,
                        0.00067695870775883013,
                    ],
                    "b": [-0, -0, 0.0],
                    "c": [
                        0.00031111847529610595,
                        0.0014902627951905339,
                        -0.00094099200035979691,
                    ],
                },
                index=["foo", "bar", "baz"],
                dtype="O",
            ),
            pd.DataFrame(
                {0: [np.nan, 2], 1: [np.nan, 3], 2: [np.nan, 4]}, dtype=object
            ),
        ],
    )
    def test_stat_operators_attempt_obj_array(self, method, df, axis):
        # GH#676
        assert df.values.dtype == np.object_
        result = getattr(df, method)(axis=axis)
        expected = getattr(df.astype("f8"), method)(axis=axis).astype(object)
        if axis in [1, "columns"] and method in ["min", "max"]:
            expected[expected.isna()] = None
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("op", ["mean", "std", "var", "skew", "kurt", "sem"])
    def test_mixed_ops(self, op):
        # GH#16116
        df = pd.DataFrame(
            {
                "int": [1, 2, 3, 4],
                "float": [1.0, 2.0, 3.0, 4.0],
                "str": ["a", "b", "c", "d"],
            }
        )
        msg = "|".join(
            [
                "Could not convert",
                "could not convert",
                "can't multiply sequence by non-int",
                "does not support",
                "Cannot perform",
            ]
        )
        with pytest.raises(TypeError, match=msg):
            getattr(df, op)()

        with pd.option_context("use_bottleneck", False):
            with pytest.raises(TypeError, match=msg):
                getattr(df, op)()

    def test_reduce_mixed_frame(self):
        # GH 6806
        df = pd.DataFrame(
            {
                "bool_data": [True, True, False, False, False],
                "int_data": [10, 20, 30, 40, 50],
                "string_data": ["a", "b", "c", "d", "e"],
            }
        )
        df.reindex(columns=["bool_data", "int_data", "string_data"])
        test = df.sum(axis=0)
        tm.assert_numpy_array_equal(
            test.values, np.array([2, 150, "abcde"], dtype=object)
        )
        alt = df.T.sum(axis=1)
        tm.assert_series_equal(test, alt)

    def test_nunique(self):
        df = pd.DataFrame({"A": [1, 1, 1], "B": [1, 2, 3], "C": [1, np.nan, 3]})
        tm.assert_series_equal(df.nunique(), pd.Series({"A": 1, "B": 3, "C": 2}))
        tm.assert_series_equal(
            df.nunique(dropna=False), pd.Series({"A": 1, "B": 3, "C": 3})
        )
        tm.assert_series_equal(df.nunique(axis=1), pd.Series([1, 2, 2]))
        tm.assert_series_equal(df.nunique(axis=1, dropna=False), pd.Series([1, 3, 2]))

    @pytest.mark.parametrize("tz", [None, "UTC"])
    def test_mean_mixed_datetime_numeric(self, tz):
        # https://github.com/pandas-dev/pandas/issues/24752
        df = pd.DataFrame({"A": [1, 1], "B": [pd.Timestamp("2000", tz=tz)] * 2})
        result = df.mean()
        expected = pd.Series([1.0, pd.Timestamp("2000", tz=tz)], index=["A", "B"])
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("tz", [None, "UTC"])
    def test_mean_includes_datetimes(self, tz):
        # https://github.com/pandas-dev/pandas/issues/24752
        # Behavior in 0.24.0rc1 was buggy.
        # As of 2.0 with numeric_only=None we do *not* drop datetime columns
        df = pd.DataFrame({"A": [pd.Timestamp("2000", tz=tz)] * 2})
        result = df.mean()

        expected = pd.Series([pd.Timestamp("2000", tz=tz)], index=["A"])
        tm.assert_series_equal(result, expected)

    def test_mean_mixed_string_decimal(self):
        # GH 11670
        # possible bug when calculating mean of DataFrame?

        d = [
            {"A": 2, "B": None, "C": Decimal("628.00")},
            {"A": 1, "B": None, "C": Decimal("383.00")},
            {"A": 3, "B": None, "C": Decimal("651.00")},
            {"A": 2, "B": None, "C": Decimal("575.00")},
            {"A": 4, "B": None, "C": Decimal("1114.00")},
            {"A": 1, "B": "TEST", "C": Decimal("241.00")},
            {"A": 2, "B": None, "C": Decimal("572.00")},
            {"A": 4, "B": None, "C": Decimal("609.00")},
            {"A": 3, "B": None, "C": Decimal("820.00")},
            {"A": 5, "B": None, "C": Decimal("1223.00")},
        ]

        df = pd.DataFrame(d)

        with pytest.raises(
            TypeError,
            match="|".join(
                [
                    "unsupported operand type",
                    "does not support",
                    "Cannot perform",
                    "Could not convert",
                ]
            ),
        ):
            df.mean()
        result = df[["A", "C"]].mean()
        expected = pd.Series([2.7, 681.6], index=["A", "C"], dtype=object)
        tm.assert_series_equal(result, expected)

    def test_var_std(self, datetime_frame):
        result = datetime_frame.std(ddof=4)
        expected = datetime_frame.apply(lambda x: x.std(ddof=4))
        tm.assert_almost_equal(result, expected)

        result = datetime_frame.var(ddof=4)
        expected = datetime_frame.apply(lambda x: x.var(ddof=4))
        tm.assert_almost_equal(result, expected)

        arr = np.repeat(np.random.default_rng(2).random((1, 1000)), 1000, 0)
        result = nanops.nanvar(arr, axis=0)
        assert not (result < 0).any()

        with pd.option_context("use_bottleneck", False):
            result = nanops.nanvar(arr, axis=0)
            assert not (result < 0).any()

    @pytest.mark.parametrize("meth", ["sem", "var", "std", "mean", "median", "skew"])
    def test_numeric_only_flag(self, meth):
        # GH 9201
        df1 = pd.DataFrame(
            np.random.default_rng(2).standard_normal((5, 3)),
            columns=["foo", "bar", "baz"],
        )
        # Cast to object to avoid implicit cast when setting entry to "100" below
        df1 = df1.astype({"foo": object})
        # set one entry to a number in str format
        df1.loc[0, "foo"] = "100"

        df2 = pd.DataFrame(
            np.random.default_rng(2).standard_normal((5, 3)),
            columns=["foo", "bar", "baz"],
        )
        # Cast to object to avoid implicit cast when setting entry to "a" below
        df2 = df2.astype({"foo": object})
        # set one entry to a non-number str
        df2.loc[0, "foo"] = "a"

        result = getattr(df1, meth)(axis=1, numeric_only=True)
        expected = getattr(df1[["bar", "baz"]], meth)(axis=1)
        tm.assert_series_equal(expected, result)

        result = getattr(df2, meth)(axis=1, numeric_only=True)
        expected = getattr(df2[["bar", "baz"]], meth)(axis=1)
        tm.assert_series_equal(expected, result)

        # GH#66302 a numeric string is no more acceptable than any other string
        msg = "Could not convert '100' to numeric"
        with pytest.raises(TypeError, match=msg):
            getattr(df1, meth)(axis=1, numeric_only=False)
        msg = "Could not convert 'a' to numeric"
        with pytest.raises(TypeError, match=msg):
            getattr(df2, meth)(axis=1, numeric_only=False)

    def test_sem(self, datetime_frame):
        result = datetime_frame.sem(ddof=4)
        expected = datetime_frame.apply(lambda x: x.std(ddof=4) / np.sqrt(len(x)))
        tm.assert_almost_equal(result, expected)

        arr = np.repeat(np.random.default_rng(2).random((1, 1000)), 1000, 0)
        result = nanops.nansem(arr, axis=0)
        assert not (result < 0).any()

        with pd.option_context("use_bottleneck", False):
            result = nanops.nansem(arr, axis=0)
            assert not (result < 0).any()

    @pytest.mark.parametrize(
        "dropna, expected",
        [
            (
                True,
                {
                    "A": [12],
                    "B": [10.0],
                    "C": [1.0],
                    "D": ["a"],
                    "E": pd.Categorical(["a"], categories=["a"]),
                    "F": pd.DatetimeIndex(["2000-01-02"], dtype="M8[ns]"),
                    "G": pd.to_timedelta(["1 days"]),
                },
            ),
            (
                False,
                {
                    "A": [12],
                    "B": [10.0],
                    "C": [np.nan],
                    "D": pd.Series([np.nan], dtype="str"),
                    "E": pd.Categorical([np.nan], categories=["a"]),
                    "F": pd.DatetimeIndex([pd.NaT], dtype="M8[ns]"),
                    "G": pd.to_timedelta([pd.NaT]).as_unit("us"),
                },
            ),
            (
                True,
                {
                    "H": [8, 9, np.nan, np.nan],
                    "I": [8, 9, np.nan, np.nan],
                    "J": [1, np.nan, np.nan, np.nan],
                    "K": pd.Categorical(
                        ["a", np.nan, np.nan, np.nan], categories=["a"]
                    ),
                    "L": pd.DatetimeIndex(
                        ["2000-01-02", "NaT", "NaT", "NaT"], dtype="M8[ns]"
                    ),
                    "M": pd.to_timedelta(["1 days", "nan", "nan", "nan"]),
                    "N": [0, 1, 2, 3],
                },
            ),
            (
                False,
                {
                    "H": [8, 9, np.nan, np.nan],
                    "I": [8, 9, np.nan, np.nan],
                    "J": [1, np.nan, np.nan, np.nan],
                    "K": pd.Categorical(
                        [np.nan, "a", np.nan, np.nan], categories=["a"]
                    ),
                    "L": pd.DatetimeIndex(
                        ["NaT", "2000-01-02", "NaT", "NaT"], dtype="M8[ns]"
                    ),
                    "M": pd.to_timedelta(["nan", "1 days", "nan", "nan"]),
                    "N": [0, 1, 2, 3],
                },
            ),
        ],
    )
    def test_mode_dropna(self, dropna, expected):
        df = pd.DataFrame(
            {
                "A": [12, 12, 19, 11],
                "B": [10, 10, np.nan, 3],
                "C": [1, np.nan, np.nan, np.nan],
                "D": pd.Series([np.nan, np.nan, "a", np.nan], dtype="str"),
                "E": pd.Categorical([np.nan, np.nan, "a", np.nan]),
                "F": pd.DatetimeIndex(
                    ["NaT", "2000-01-02", "NaT", "NaT"], dtype="M8[ns]"
                ),
                "G": pd.to_timedelta(["1 days", "nan", "nan", "nan"]),
                "H": [8, 8, 9, 9],
                "I": [9, 9, 8, 8],
                "J": [1, 1, np.nan, np.nan],
                "K": pd.Categorical(["a", np.nan, "a", np.nan]),
                "L": pd.DatetimeIndex(
                    ["2000-01-02", "2000-01-02", "NaT", "NaT"], dtype="M8[ns]"
                ),
                "M": pd.to_timedelta(["1 days", "nan", "1 days", "nan"]),
                "N": np.arange(4, dtype="int64"),
            }
        )

        result = df[sorted(expected.keys())].mode(dropna=dropna)
        expected = pd.DataFrame(expected)
        tm.assert_frame_equal(result, expected)

    def test_mode_sort_with_na(self, using_infer_string):
        df = pd.DataFrame({"A": [np.nan, np.nan, "a", "a"]})
        expected = pd.DataFrame({"A": ["a", np.nan]})
        result = df.mode(dropna=False)
        tm.assert_frame_equal(result, expected)

    def test_mode_empty_df(self):
        df = pd.DataFrame([], columns=["a", "b"])
        expected = df.copy()
        result = df.mode()
        tm.assert_frame_equal(result, expected)

    def test_operators_timedelta64(self):
        df = pd.DataFrame(
            {
                "A": pd.date_range("2012-1-1", periods=3, freq="D", unit="ns"),
                "B": pd.date_range("2012-1-2", periods=3, freq="D", unit="ns"),
                "C": pd.Timestamp("20120101") - timedelta(minutes=5, seconds=5),
            }
        )

        diffs = pd.DataFrame({"A": df["A"] - df["C"], "B": df["A"] - df["B"]})

        # min
        result = diffs.min()
        assert result.iloc[0] == diffs.loc[0, "A"]
        assert result.iloc[1] == diffs.loc[0, "B"]

        result = diffs.min(axis=1)
        assert (result == diffs.loc[0, "B"]).all()

        # max
        result = diffs.max()
        assert result.iloc[0] == diffs.loc[2, "A"]
        assert result.iloc[1] == diffs.loc[2, "B"]

        result = diffs.max(axis=1)
        assert (result == diffs["A"]).all()

        # abs
        result = diffs.abs()
        result2 = abs(diffs)
        expected = pd.DataFrame({"A": df["A"] - df["C"], "B": df["B"] - df["A"]})
        tm.assert_frame_equal(result, expected)
        tm.assert_frame_equal(result2, expected)

        # mixed frame
        mixed = diffs.copy()
        mixed["C"] = "foo"
        mixed["D"] = 1
        mixed["E"] = 1.0
        mixed["F"] = pd.Timestamp("20130101")

        # results in an object array
        result = mixed.min()
        expected = pd.Series(
            [
                pd.Timedelta(timedelta(seconds=5 * 60 + 5)),
                pd.Timedelta(timedelta(days=-1)),
                "foo",
                1,
                1.0,
                pd.Timestamp("20130101"),
            ],
            index=mixed.columns,
        )
        tm.assert_series_equal(result, expected)

        # excludes non-numeric
        result = mixed.min(axis=1, numeric_only=True)
        expected = pd.Series([1, 1, 1.0])
        tm.assert_series_equal(result, expected)

        # works when only those columns are selected
        result = mixed[["A", "B"]].min(axis=1)
        expected = pd.Series([timedelta(days=-1)] * 3, dtype="m8[ns]")
        tm.assert_series_equal(result, expected)

        result = mixed[["A", "B"]].min()
        expected = pd.Series(
            [timedelta(seconds=5 * 60 + 5), timedelta(days=-1)],
            index=["A", "B"],
            dtype="m8[ns]",
        )
        tm.assert_series_equal(result, expected)

        # GH 3106
        df = pd.DataFrame(
            {
                "time": pd.date_range("20130102", periods=5, unit="ns"),
                "time2": pd.date_range("20130105", periods=5, unit="ns"),
            }
        )
        df["off1"] = df["time2"] - df["time"]
        assert df["off1"].dtype == "timedelta64[ns]"

        df["off2"] = df["time"] - df["time2"]
        df._consolidate_inplace()
        assert df["off1"].dtype == "timedelta64[ns]"
        assert df["off2"].dtype == "timedelta64[ns]"

    def test_std_timedelta64_skipna_false(self):
        # GH#37392
        tdi = pd.timedelta_range("1 Day", periods=10)
        df = pd.DataFrame({"A": tdi, "B": tdi}, copy=True)
        df.iloc[-2, -1] = pd.NaT

        result = df.std(skipna=False)
        expected = pd.Series(
            [df["A"].std(), pd.NaT], index=["A", "B"], dtype="timedelta64[us]"
        )
        tm.assert_series_equal(result, expected)

        result = df.std(axis=1, skipna=False)
        expected = pd.Series(
            [pd.Timedelta(0)] * 8 + [pd.NaT, pd.Timedelta(0)], dtype="m8[us]"
        )
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "values", [["2022-01-01", "2022-01-02", pd.NaT, "2022-01-03"], 4 * [pd.NaT]]
    )
    def test_std_datetime64_with_nat(self, values, skipna, request, unit):
        # GH#51335
        dti = pd.to_datetime(values).as_unit(unit)
        df = pd.DataFrame({"a": dti})
        result = df.std(skipna=skipna)
        if not skipna or all(value is pd.NaT for value in values):
            expected = pd.Series({"a": pd.NaT}, dtype=f"timedelta64[{unit}]")
        else:
            expected = pd.Series({"a": "1 days"}, dtype=f"timedelta64[{unit}]")
        tm.assert_series_equal(result, expected)

    def test_sum_corner(self):
        empty_frame = pd.DataFrame()

        axis0 = empty_frame.sum(axis=0)
        axis1 = empty_frame.sum(axis=1)
        assert isinstance(axis0, pd.Series)
        assert isinstance(axis1, pd.Series)
        assert len(axis0) == 0
        assert len(axis1) == 0

    @pytest.mark.parametrize(
        "index",
        [
            pd.RangeIndex(0),
            pd.DatetimeIndex([]),
            pd.Index([], dtype=np.int64),
            pd.Index([], dtype=np.float64),
            pd.DatetimeIndex([], freq="ME"),
            pd.PeriodIndex([], freq="D"),
        ],
    )
    def test_axis_1_empty(self, all_reductions, index):
        df = pd.DataFrame(columns=["a"], index=index)
        result = getattr(df, all_reductions)(axis=1)
        if all_reductions in ("any", "all"):
            expected_dtype = "bool"
        elif all_reductions == "count":
            expected_dtype = "int64"
        else:
            expected_dtype = "object"
        expected = pd.Series([], index=index, dtype=expected_dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("min_count", [0, 1])
    def test_axis_1_sum_na(self, string_dtype_no_object, skipna, min_count):
        # https://github.com/pandas-dev/pandas/issues/60229
        dtype = string_dtype_no_object
        df = pd.DataFrame({"a": [pd.NA]}, dtype=dtype)
        result = df.sum(axis=1, skipna=skipna, min_count=min_count)
        value = "" if skipna and min_count == 0 else pd.NA
        expected = pd.Series([value], dtype=dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "min_count, expected",
        [
            (1, [7.0, 3.0, np.nan]),
            (2, [7.0, np.nan, np.nan]),
            (3, [np.nan, np.nan, np.nan]),
        ],
    )
    def test_axis_1_sum_min_count_sparse(self, min_count, expected):
        # https://github.com/pandas-dev/pandas/issues/55123
        df = pd.DataFrame({"A": [2.0, 3.0, np.nan], "B": [5.0, np.nan, np.nan]}).astype(
            pd.SparseDtype("float64")
        )
        result = df.sum(axis=1, skipna=True, min_count=min_count)
        expected = pd.Series(expected, dtype="float64")
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("method, unit", [("sum", 0), ("prod", 1)])
    @pytest.mark.parametrize("numeric_only", [True, False])
    def test_sum_prod_nanops(self, method, unit, numeric_only):
        idx = ["a", "b", "c"]
        df = pd.DataFrame(
            {"a": [unit, unit], "b": [unit, np.nan], "c": [np.nan, np.nan]}
        )
        # The default
        result = getattr(df, method)(numeric_only=numeric_only)
        expected = pd.Series([unit, unit, unit], index=idx, dtype="float64")
        tm.assert_series_equal(result, expected)

        # min_count=1
        result = getattr(df, method)(numeric_only=numeric_only, min_count=1)
        expected = pd.Series([unit, unit, np.nan], index=idx)
        tm.assert_series_equal(result, expected)

        # min_count=0
        result = getattr(df, method)(numeric_only=numeric_only, min_count=0)
        expected = pd.Series([unit, unit, unit], index=idx, dtype="float64")
        tm.assert_series_equal(result, expected)

        result = getattr(df.iloc[1:], method)(numeric_only=numeric_only, min_count=1)
        expected = pd.Series([unit, np.nan, np.nan], index=idx)
        tm.assert_series_equal(result, expected)

        # min_count > 1
        df = pd.DataFrame({"A": [unit] * 10, "B": [unit] * 5 + [np.nan] * 5})
        result = getattr(df, method)(numeric_only=numeric_only, min_count=5)
        expected = pd.Series(result, index=["A", "B"])
        tm.assert_series_equal(result, expected)

        result = getattr(df, method)(numeric_only=numeric_only, min_count=6)
        expected = pd.Series(result, index=["A", "B"])
        tm.assert_series_equal(result, expected)

    def test_sum_nanops_timedelta(self):
        # prod isn't defined on timedeltas
        idx = ["a", "b", "c"]
        df = pd.DataFrame({"a": [0, 0], "b": [0, np.nan], "c": [np.nan, np.nan]})

        df2 = df.apply(pd.to_timedelta)

        # 0 by default
        result = df2.sum()
        expected = pd.Series([0, 0, 0], dtype="m8[ns]", index=idx)
        tm.assert_series_equal(result, expected)

        # min_count=0
        result = df2.sum(min_count=0)
        tm.assert_series_equal(result, expected)

        # min_count=1
        result = df2.sum(min_count=1)
        expected = pd.Series([0, 0, np.nan], dtype="m8[ns]", index=idx)
        tm.assert_series_equal(result, expected)

    def test_sum_nanops_min_count(self):
        # https://github.com/pandas-dev/pandas/issues/39738
        df = pd.DataFrame({"x": [1, 2, 3], "y": [4, 5, 6]})
        result = df.sum(min_count=10)
        expected = pd.Series([np.nan, np.nan], index=["x", "y"])
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("float_type", ["float16", "float32", "float64"])
    @pytest.mark.parametrize(
        "kwargs, expected_result",
        [
            ({"axis": 1, "min_count": 2}, [3.2, 5.3, np.nan]),
            ({"axis": 1, "min_count": 3}, [np.nan, np.nan, np.nan]),
            ({"axis": 1, "skipna": False}, [3.2, 5.3, np.nan]),
        ],
    )
    def test_sum_nanops_dtype_min_count(self, float_type, kwargs, expected_result):
        # GH#46947
        df = pd.DataFrame(
            {"a": [1.0, 2.3, 4.4], "b": [2.2, 3, np.nan]}, dtype=float_type
        )
        result = df.sum(**kwargs)
        # GH#43929 float16 upcasts to float64 in nansum to avoid overflow
        expected = pd.Series(expected_result, dtype=float_type)
        if float_type == "float16":
            expected = expected.astype("float64")
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("float_type", ["float16", "float32", "float64"])
    @pytest.mark.parametrize(
        "kwargs, expected_result",
        [
            ({"axis": 1, "min_count": 2}, [2.0, 4.0, np.nan]),
            ({"axis": 1, "min_count": 3}, [np.nan, np.nan, np.nan]),
            ({"axis": 1, "skipna": False}, [2.0, 4.0, np.nan]),
        ],
    )
    def test_prod_nanops_dtype_min_count(self, float_type, kwargs, expected_result):
        # GH#46947
        df = pd.DataFrame(
            {"a": [1.0, 2.0, 4.4], "b": [2.0, 2.0, np.nan]}, dtype=float_type
        )
        result = df.prod(**kwargs)
        expected = pd.Series(expected_result).astype(float_type)
        tm.assert_series_equal(result, expected)

    def test_sum_object(self, float_frame):
        values = float_frame.values.astype(int)
        frame = pd.DataFrame(
            values, index=float_frame.index, columns=float_frame.columns
        )
        deltas = frame * timedelta(1)
        deltas.sum()

    def test_sum_bool(self, float_frame):
        # ensure this works, bug report
        bools = np.isnan(float_frame)
        bools.sum(axis=1)
        bools.sum(axis=0)

    def test_sum_mixed_datetime(self):
        # GH#30886
        df = pd.DataFrame(
            {"A": pd.date_range("2000", periods=4), "B": [1, 2, 3, 4]}
        ).reindex([2, 3, 4])
        with pytest.raises(TypeError, match="does not support operation 'sum'"):
            df.sum()

    def test_mean_corner(self, float_frame):
        # take mean of boolean column
        float_frame["bool"] = float_frame["A"] > 0
        means = float_frame.mean(axis=0)
        assert means["bool"] == float_frame["bool"].values.mean()

    def test_mean_datetimelike(self):
        # GH#24757 check that datetimelike are excluded by default, handled
        #  correctly with numeric_only=True
        #  As of 2.0, datetimelike are *not* excluded with numeric_only=None

        df = pd.DataFrame(
            {
                "A": np.arange(3),
                "B": pd.date_range("2016-01-01", periods=3),
                "C": pd.timedelta_range("1D", periods=3),
                "D": pd.period_range("2016", periods=3, freq="Y"),
            }
        )
        result = df.mean(numeric_only=True)
        expected = pd.Series({"A": 1.0})
        tm.assert_series_equal(result, expected)

        with pytest.raises(TypeError, match="mean is not implemented for PeriodArray"):
            df.mean()

    def test_mean_datetimelike_numeric_only_false(self):
        df = pd.DataFrame(
            {
                "A": np.arange(3),
                "B": pd.date_range("2016-01-01", periods=3),
                "C": pd.timedelta_range("1D", periods=3),
            }
        )

        # datetime(tz) and timedelta work
        result = df.mean(numeric_only=False)
        expected = pd.Series({"A": 1, "B": df.loc[1, "B"], "C": df.loc[1, "C"]})
        tm.assert_series_equal(result, expected)

        # mean of period is not allowed
        df["D"] = pd.period_range("2016", periods=3, freq="Y")

        with pytest.raises(TypeError, match="mean is not implemented for Period"):
            df.mean(numeric_only=False)

    def test_mean_extensionarray_numeric_only_true(self):
        # https://github.com/pandas-dev/pandas/issues/33256
        arr = np.random.default_rng(2).integers(1000, size=(10, 5))
        df = pd.DataFrame(arr, dtype="Int64")
        result = df.mean(numeric_only=True)
        expected = pd.DataFrame(arr).mean().astype("Float64")
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "meth", ["std", "var", "mean", "median", "sem", "skew", "kurt"]
    )
    def test_stats_mixed_type(self, float_string_frame, meth):
        msg = "Could not convert 'bar' to numeric"
        with pytest.raises(TypeError, match=msg):
            getattr(float_string_frame, meth)(axis=1)

    def test_sum_bools(self):
        df = pd.DataFrame(index=range(1), columns=range(10))
        bools = pd.isna(df)
        assert bools.sum(axis=1)[0] == 10

    @pytest.mark.parametrize(
        "input_data, expected_data",
        [
            ({"a": ["483", "3"], "b": ["94", "759"]}, ["48394", "3759"]),
            (
                {"a": ["483.948", "3.0"], "b": ["94.2", "759.93"]},
                ["483.94894.2", "3.0759.93"],
            ),
            ({"a": ["483", "3.0"], "b": ["94.2", "79"]}, ["48394.2", "3.079"]),
        ],
    )
    def test_sum_string_dtype_coercion(self, input_data, expected_data):
        # GH#22642
        # Check that summing numeric strings results in concatenation
        # and not conversion to dtype int64 or float64
        df = pd.DataFrame(input_data)
        expected = pd.Series(expected_data)
        result = df.sum(axis=1)
        tm.assert_series_equal(result, expected)

    # ----------------------------------------------------------------------
    # Index of max / min

    @pytest.mark.parametrize("axis", [0, 1])
    def test_idxmin(self, float_frame, int_frame, skipna, axis):
        frame = float_frame
        frame.iloc[5:10] = np.nan
        frame.iloc[15:20, -2:] = np.nan
        for df in [frame, int_frame]:
            if (not skipna or axis == 1) and df is not int_frame:
                if skipna:
                    msg = "Encountered all NA values"
                else:
                    msg = "Encountered an NA value"
                with pytest.raises(ValueError, match=msg):
                    df.idxmin(axis=axis, skipna=skipna)
                with pytest.raises(ValueError, match=msg):
                    df.idxmin(axis=axis, skipna=skipna)
            else:
                result = df.idxmin(axis=axis, skipna=skipna)
                expected = df.apply(pd.Series.idxmin, axis=axis, skipna=skipna)
                expected = expected.astype(df.index.dtype)
                tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("axis", [0, 1])
    def test_idxmin_empty(self, index, skipna, axis):
        # GH53265
        if axis == 0:
            frame = pd.DataFrame(index=index)
        else:
            frame = pd.DataFrame(columns=index)

        result = frame.idxmin(axis=axis, skipna=skipna)
        expected = pd.Series(dtype=index.dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("numeric_only", [True, False])
    def test_idxmin_numeric_only(self, numeric_only):
        df = pd.DataFrame({"a": [2, 3, 1], "b": [2, 1, 1], "c": list("xyx")})
        result = df.idxmin(numeric_only=numeric_only)
        if numeric_only:
            expected = pd.Series([2, 1], index=["a", "b"])
        else:
            expected = pd.Series([2, 1, 0], index=["a", "b", "c"])
        tm.assert_series_equal(result, expected)

    def test_idxmin_axis_2(self, float_frame):
        frame = float_frame
        msg = "No axis named 2 for object type DataFrame"
        with pytest.raises(ValueError, match=msg):
            frame.idxmin(axis=2)

    @pytest.mark.parametrize("axis", [0, 1])
    def test_idxmax(self, float_frame, int_frame, skipna, axis):
        frame = float_frame
        frame.iloc[5:10] = np.nan
        frame.iloc[15:20, -2:] = np.nan
        for df in [frame, int_frame]:
            if (skipna is False or axis == 1) and df is frame:
                if skipna:
                    msg = "Encountered all NA values"
                else:
                    msg = "Encountered an NA value"
                with pytest.raises(ValueError, match=msg):
                    df.idxmax(axis=axis, skipna=skipna)
                return

            result = df.idxmax(axis=axis, skipna=skipna)
            expected = df.apply(pd.Series.idxmax, axis=axis, skipna=skipna)
            expected = expected.astype(df.index.dtype)
            tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("axis", [0, 1])
    def test_idxmax_empty(self, index, skipna, axis):
        # GH53265
        if axis == 0:
            frame = pd.DataFrame(index=index)
        else:
            frame = pd.DataFrame(columns=index)

        result = frame.idxmax(axis=axis, skipna=skipna)
        expected = pd.Series(dtype=index.dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("numeric_only", [True, False])
    def test_idxmax_numeric_only(self, numeric_only):
        df = pd.DataFrame({"a": [2, 3, 1], "b": [2, 1, 1], "c": list("xyx")})
        result = df.idxmax(numeric_only=numeric_only)
        if numeric_only:
            expected = pd.Series([1, 0], index=["a", "b"])
        else:
            expected = pd.Series([1, 0, 1], index=["a", "b", "c"])
        tm.assert_series_equal(result, expected)

    def test_idxmax_arrow_types(self):
        # GH#55368
        pytest.importorskip("pyarrow")

        df = pd.DataFrame({"a": [2, 3, 1], "b": [2, 1, 1]}, dtype="int64[pyarrow]")
        result = df.idxmax()
        expected = pd.Series([1, 0], index=["a", "b"])
        tm.assert_series_equal(result, expected)

        result = df.idxmin()
        expected = pd.Series([2, 1], index=["a", "b"])
        tm.assert_series_equal(result, expected)

        df = pd.DataFrame({"a": ["b", "c", "a"]}, dtype="string[pyarrow]")
        result = df.idxmax(numeric_only=False)
        expected = pd.Series([1], index=["a"])
        tm.assert_series_equal(result, expected)

        result = df.idxmin(numeric_only=False)
        expected = pd.Series([2], index=["a"])
        tm.assert_series_equal(result, expected)

    def test_idxmax_axis_2(self, float_frame):
        frame = float_frame
        msg = "No axis named 2 for object type DataFrame"
        with pytest.raises(ValueError, match=msg):
            frame.idxmax(axis=2)

    def test_idxmax_mixed_dtype(self):
        # don't cast to object, which would raise in nanops
        dti = pd.date_range("2016-01-01", periods=3)
        df = pd.DataFrame({1: [0, 2, 1], 2: range(3)[::-1], 3: dti})

        result = df.idxmax()
        expected = pd.Series([1, 0, 2], index=range(1, 4))
        tm.assert_series_equal(result, expected)

        result = df.idxmin()
        expected = pd.Series([0, 2, 0], index=range(1, 4))
        tm.assert_series_equal(result, expected)

        # with NaTs
        df.loc[0, 3] = pd.NaT
        result = df.idxmax()
        expected = pd.Series([1, 0, 2], index=range(1, 4))
        tm.assert_series_equal(result, expected)

        result = df.idxmin()
        expected = pd.Series([0, 2, 1], index=range(1, 4))
        tm.assert_series_equal(result, expected)

        # with multi-column dt64 block
        df[4] = dti[::-1]
        df._consolidate_inplace()

        result = df.idxmax()
        expected = pd.Series([1, 0, 2, 0], index=range(1, 5))
        tm.assert_series_equal(result, expected)

        result = df.idxmin()
        expected = pd.Series([0, 2, 1, 2], index=range(1, 5))
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "op, expected_value",
        [("idxmax", [0, 4]), ("idxmin", [0, 5])],
    )
    def test_idxmax_idxmin_convert_dtypes(self, op, expected_value):
        # GH 40346
        df = pd.DataFrame(
            {
                "ID": [100, 100, 100, 200, 200, 200],
                "value": [0, 0, 0, 1, 2, 0],
            },
            dtype="Int64",
        )
        df = df.groupby("ID")

        result = getattr(df, op)()
        expected = pd.DataFrame(
            {"value": expected_value},
            index=pd.Index([100, 200], name="ID", dtype="Int64"),
        )
        tm.assert_frame_equal(result, expected)

    def test_idxmax_dt64_multicolumn_axis1(self):
        dti = pd.date_range("2016-01-01", periods=3)
        df = pd.DataFrame({3: dti, 4: dti[::-1]}, copy=True)
        df.iloc[0, 0] = pd.NaT

        df._consolidate_inplace()

        result = df.idxmax(axis=1)
        expected = pd.Series([4, 3, 3])
        tm.assert_series_equal(result, expected)

        result = df.idxmin(axis=1)
        expected = pd.Series([4, 3, 4])
        tm.assert_series_equal(result, expected)

    # ----------------------------------------------------------------------
    # Logical reductions

    @pytest.mark.parametrize("axis", [0, 1])
    @pytest.mark.parametrize("bool_only", [False, True])
    def test_any_all_mixed_float(
        self, all_boolean_reductions, axis, bool_only, float_string_frame
    ):
        # make sure op works on mixed-type frame
        mixed = float_string_frame
        mixed["_bool_"] = np.random.default_rng(2).standard_normal(len(mixed)) > 0.5

        getattr(mixed, all_boolean_reductions)(axis=axis, bool_only=bool_only)

    @pytest.mark.parametrize("axis", [0, 1])
    def test_any_all_bool_with_na(
        self, all_boolean_reductions, axis, bool_frame_with_na
    ):
        getattr(bool_frame_with_na, all_boolean_reductions)(axis=axis, bool_only=False)

    def test_any_all_bool_frame(self, all_boolean_reductions, bool_frame_with_na):
        # GH#12863: numpy gives back non-boolean data for object type
        # so fill NaNs to compare with pandas behavior
        frame = bool_frame_with_na.fillna(True)
        alternative = getattr(np, all_boolean_reductions)
        f = getattr(frame, all_boolean_reductions)

        def skipna_wrapper(x):
            nona = x.dropna().values
            return alternative(nona)

        def wrapper(x):
            return alternative(x.values)

        result0 = f(axis=0, skipna=False)
        result1 = f(axis=1, skipna=False)

        tm.assert_series_equal(result0, frame.apply(wrapper))
        tm.assert_series_equal(result1, frame.apply(wrapper, axis=1))

        result0 = f(axis=0)
        result1 = f(axis=1)

        tm.assert_series_equal(result0, frame.apply(skipna_wrapper))
        tm.assert_series_equal(
            result1, frame.apply(skipna_wrapper, axis=1), check_dtype=False
        )

        # bad axis
        with pytest.raises(ValueError, match="No axis named 2"):
            f(axis=2)

        # all NA case
        all_na = frame * np.nan
        r0 = getattr(all_na, all_boolean_reductions)(axis=0)
        r1 = getattr(all_na, all_boolean_reductions)(axis=1)
        if all_boolean_reductions == "any":
            assert not r0.any()
            assert not r1.any()
        else:
            assert r0.all()
            assert r1.all()

    def test_any_all_extra(self, using_python_scalars):
        df = pd.DataFrame(
            {
                "A": [True, False, False],
                "B": [True, True, False],
                "C": [True, True, True],
            },
            index=["a", "b", "c"],
        )
        result = df[["A", "B"]].any(axis=1)
        expected = pd.Series([True, True, False], index=["a", "b", "c"])
        tm.assert_series_equal(result, expected)

        result = df[["A", "B"]].any(axis=1, bool_only=True)
        tm.assert_series_equal(result, expected)

        result = df.all(axis=1)
        expected = pd.Series([True, False, False], index=["a", "b", "c"])
        tm.assert_series_equal(result, expected)

        result = df.all(axis=1, bool_only=True)
        tm.assert_series_equal(result, expected)

        # Axis is None
        result = df.all(axis=None)
        if not using_python_scalars:
            result = result.item()
        assert result is False

        result = df.any(axis=None)
        if not using_python_scalars:
            result = result.item()
        assert result is True

        result = df[["C"]].all(axis=None)
        if not using_python_scalars:
            result = result.item()
        assert result is True

    @pytest.mark.parametrize("axis", [0, 1])
    def test_any_all_object_dtype(self, axis, all_boolean_reductions, skipna):
        # GH#35450
        df = pd.DataFrame(
            data=[
                [1, np.nan, np.nan, True],
                [np.nan, 2, np.nan, True],
                [np.nan, np.nan, np.nan, True],
                [np.nan, np.nan, "5", np.nan],
            ]
        )
        result = getattr(df, all_boolean_reductions)(axis=axis, skipna=skipna)
        expected = pd.Series([True, True, True, True])
        tm.assert_series_equal(result, expected)

    def test_any_datetime(self):
        # GH 23070
        float_data = [1, np.nan, 3, np.nan]
        datetime_data = [
            pd.Timestamp("1960-02-15"),
            pd.Timestamp("1960-02-16"),
            pd.NaT,
            pd.NaT,
        ]
        df = pd.DataFrame({"A": float_data, "B": datetime_data})

        msg = "'any' with datetime64 dtypes is not supported"
        with pytest.raises(TypeError, match=msg):
            df.any(axis=1)

    def test_any_all_bool_only(self):
        # GH 25101
        df = pd.DataFrame(
            {"col1": [1, 2, 3], "col2": [4, 5, 6], "col3": [None, None, None]},
            columns=pd.Index(["col1", "col2", "col3"], dtype=object),
        )

        result = df.all(bool_only=True)
        expected = pd.Series(dtype=np.bool_, index=[])
        tm.assert_series_equal(result, expected)

        df = pd.DataFrame(
            {
                "col1": [1, 2, 3],
                "col2": [4, 5, 6],
                "col3": [None, None, None],
                "col4": [False, False, True],
            }
        )

        result = df.all(bool_only=True)
        expected = pd.Series({"col4": False})
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "func, data, expected",
        [
            (np.any, {}, False),
            (np.all, {}, True),
            (np.any, {"A": []}, False),
            (np.all, {"A": []}, True),
            (np.any, {"A": [False, False]}, False),
            (np.all, {"A": [False, False]}, False),
            (np.any, {"A": [True, False]}, True),
            (np.all, {"A": [True, False]}, False),
            (np.any, {"A": [True, True]}, True),
            (np.all, {"A": [True, True]}, True),
            (np.any, {"A": [False], "B": [False]}, False),
            (np.all, {"A": [False], "B": [False]}, False),
            (np.any, {"A": [False, False], "B": [False, True]}, True),
            (np.all, {"A": [False, False], "B": [False, True]}, False),
            # other types
            (np.all, {"A": pd.Series([0.0, 1.0], dtype="float")}, False),
            (np.any, {"A": pd.Series([0.0, 1.0], dtype="float")}, True),
            (np.all, {"A": pd.Series([0, 1], dtype=int)}, False),
            (np.any, {"A": pd.Series([0, 1], dtype=int)}, True),
            pytest.param(np.all, {"A": pd.Series([0, 1], dtype="M8[ns]")}, False),
            pytest.param(np.all, {"A": pd.Series([0, 1], dtype="M8[ns, UTC]")}, False),
            pytest.param(np.any, {"A": pd.Series([0, 1], dtype="M8[ns]")}, True),
            pytest.param(np.any, {"A": pd.Series([0, 1], dtype="M8[ns, UTC]")}, True),
            pytest.param(np.all, {"A": pd.Series([1, 2], dtype="M8[ns]")}, True),
            pytest.param(np.all, {"A": pd.Series([1, 2], dtype="M8[ns, UTC]")}, True),
            pytest.param(np.any, {"A": pd.Series([1, 2], dtype="M8[ns]")}, True),
            pytest.param(np.any, {"A": pd.Series([1, 2], dtype="M8[ns, UTC]")}, True),
            pytest.param(np.all, {"A": pd.Series([0, 1], dtype="m8[ns]")}, False),
            pytest.param(np.any, {"A": pd.Series([0, 1], dtype="m8[ns]")}, True),
            pytest.param(np.all, {"A": pd.Series([1, 2], dtype="m8[ns]")}, True),
            pytest.param(np.any, {"A": pd.Series([1, 2], dtype="m8[ns]")}, True),
            # np.all on Categorical raises, so the reduction drops the
            #  column, so all is being done on an empty Series, so is True
            (np.all, {"A": pd.Series([0, 1], dtype="category")}, True),
            (np.any, {"A": pd.Series([0, 1], dtype="category")}, False),
            (np.all, {"A": pd.Series([1, 2], dtype="category")}, True),
            (np.any, {"A": pd.Series([1, 2], dtype="category")}, False),
            # Mix GH#21484
            pytest.param(
                np.all,
                {
                    "A": pd.Series([10, 20], dtype="M8[ns]"),
                    "B": pd.Series([10, 20], dtype="m8[ns]"),
                },
                True,
            ),
        ],
    )
    def test_any_all_np_func(self, func, data, expected, using_python_scalars):
        # GH 19976
        data = pd.DataFrame(data)

        if any(isinstance(x, pd.CategoricalDtype) for x in data.dtypes):
            with pytest.raises(
                TypeError, match=".* dtype category does not support operation"
            ):
                func(data)

            # method version
            with pytest.raises(
                TypeError, match=".* dtype category does not support operation"
            ):
                getattr(pd.DataFrame(data), func.__name__)(axis=None)
        if data.dtypes.apply(lambda x: x.kind == "M").any():
            # GH#34479
            msg = "'(any|all)' with datetime64 dtypes is not supported"
            with pytest.raises(TypeError, match=msg):
                func(data)

            # method version
            with pytest.raises(TypeError, match=msg):
                getattr(pd.DataFrame(data), func.__name__)(axis=None)

        elif data.dtypes.apply(lambda x: x != "category").any():
            result = func(data)
            if using_python_scalars:
                assert result is expected
            else:
                assert isinstance(result, np.bool_)
                assert result.item() is expected

            # method version
            result = getattr(pd.DataFrame(data), func.__name__)(axis=None)
            if using_python_scalars:
                assert result is expected
            else:
                assert isinstance(result, np.bool_)
                assert result.item() is expected

    def test_any_all_object(self, using_python_scalars):
        # GH 19976
        result = np.all(pd.DataFrame(columns=["a", "b"]))
        if not using_python_scalars:
            result = result.item()
        assert result is True

        result = np.any(pd.DataFrame(columns=["a", "b"]))
        if not using_python_scalars:
            result = result.item()
        assert result is False

    def test_any_all_object_bool_only(self):
        df = pd.DataFrame({"A": ["foo", 2], "B": [True, False]}).astype(object)
        df._consolidate_inplace()
        df["C"] = pd.Series([True, True])

        # Categorical of bools is _not_ considered booly
        df["D"] = df["C"].astype("category")

        # The underlying bug is in DataFrame._get_bool_data, so we check
        #  that while we're here
        res = df._get_bool_data()
        expected = df[["C"]]
        tm.assert_frame_equal(res, expected)

        res = df.all(bool_only=True, axis=0)
        expected = pd.Series([True], index=["C"])
        tm.assert_series_equal(res, expected)

        # operating on a subset of columns should not produce a _larger_ Series
        res = df[["B", "C"]].all(bool_only=True, axis=0)
        tm.assert_series_equal(res, expected)

        assert df.all(bool_only=True, axis=None)

        res = df.any(bool_only=True, axis=0)
        expected = pd.Series([True], index=["C"])
        tm.assert_series_equal(res, expected)

        # operating on a subset of columns should not produce a _larger_ Series
        res = df[["C"]].any(bool_only=True, axis=0)
        tm.assert_series_equal(res, expected)

        assert df.any(bool_only=True, axis=None)

    @pytest.mark.parametrize(
        "dtype",
        [
            "boolean",
            "Int8",
            "Int16",
            "Int32",
            "Int64",
            "UInt8",
            "UInt16",
            "UInt32",
            "UInt64",
            "Float32",
            "Float64",
        ],
    )
    @pytest.mark.parametrize(
        "data, op, expected_value",
        [
            ([False, None], "any", pd.NA),
            ([True, None], "all", pd.NA),
            ([None, None], "any", pd.NA),
            ([None, None], "all", pd.NA),
            ([True, None], "any", True),
        ],
    )
    def test_any_all_skipna_false_nullable(self, dtype, data, op, expected_value):
        # GH#65710
        if dtype != "boolean":
            data = [(0 if v is False else 1 if v is True else None) for v in data]
        arr = pd.array(data, dtype=dtype)
        df = pd.DataFrame({"a": arr})

        result = getattr(df, op)(skipna=False)
        expected = pd.Series([expected_value], index=["a"], dtype="boolean")
        tm.assert_series_equal(result, expected)

        ser_result = getattr(pd.Series(arr), op)(skipna=False)
        if expected_value is pd.NA:
            assert ser_result is pd.NA
        else:
            assert ser_result == expected_value

    def test_any_skipna_false_axis_none_nullable(self):
        # GH#65710
        df = pd.DataFrame({"a": pd.array([False, None], dtype="boolean")})
        assert df.any(skipna=False, axis=None) is pd.NA

    # ---------------------------------------------------------------------
    # Unsorted

    def test_series_broadcasting(self):
        # smoke test for numpy warnings
        # GH 16378, GH 16306
        df = pd.DataFrame([1.0, 1.0, 1.0])
        df_nan = pd.DataFrame({"A": [np.nan, 2.0, np.nan]})
        s = pd.Series([1, 1, 1])
        s_nan = pd.Series([np.nan, np.nan, 1])

        with tm.assert_produces_warning(None):
            df_nan.clip(lower=s, axis=0)
            for op in ["lt", "le", "gt", "ge", "eq", "ne"]:
                getattr(df, op)(s_nan, axis=0)


class TestDataFrameReductions:
    def test_min_max_dt64_with_NaT(self):
        # Both NaT and Timestamp are in DataFrame.
        df = pd.DataFrame({"foo": [pd.NaT, pd.NaT, pd.Timestamp("2012-05-01")]})

        res = df.min()
        exp = pd.Series([pd.Timestamp("2012-05-01")], index=["foo"])
        tm.assert_series_equal(res, exp)

        res = df.max()
        exp = pd.Series([pd.Timestamp("2012-05-01")], index=["foo"])
        tm.assert_series_equal(res, exp)

        # GH12941, only NaTs are in DataFrame.
        df = pd.DataFrame({"foo": [pd.NaT, pd.NaT]})

        res = df.min()
        exp = pd.Series([pd.NaT], index=["foo"])
        tm.assert_series_equal(res, exp)

        res = df.max()
        exp = pd.Series([pd.NaT], index=["foo"])
        tm.assert_series_equal(res, exp)

    def test_min_max_dt64_with_NaT_precision(self):
        # GH#60646 Make sure the reduction doesn't cast input timestamps to
        # float and lose precision.
        df = pd.DataFrame(
            {"foo": [pd.NaT, pd.NaT, pd.Timestamp("2012-05-01 09:20:00.123456789")]},
            dtype="datetime64[ns]",
        )

        res = df.min(axis=1)
        exp = df.foo.rename(None)
        tm.assert_series_equal(res, exp)

        res = df.max(axis=1)
        exp = df.foo.rename(None)
        tm.assert_series_equal(res, exp)

    def test_min_max_td64_with_NaT_precision(self):
        # GH#60646 Make sure the reduction doesn't cast input timedeltas to
        # float and lose precision.
        df = pd.DataFrame(
            {
                "foo": [
                    pd.NaT,
                    pd.NaT,
                    pd.to_timedelta("10000 days 06:05:01.123456789"),
                ],
            },
            dtype="timedelta64[ns]",
        )

        res = df.min(axis=1)
        exp = df.foo.rename(None)
        tm.assert_series_equal(res, exp)

        res = df.max(axis=1)
        exp = df.foo.rename(None)
        tm.assert_series_equal(res, exp)

    def test_min_max_dt64_with_NaT_skipna_false(self, request, tz_naive_fixture):
        # GH#36907
        tz = tz_naive_fixture
        if isinstance(tz, tzlocal) and is_platform_windows():
            pytest.skip(
                "GH#37659 OSError raised within tzlocal bc Windows "
                "chokes in times before 1970-01-01"
            )

        df = pd.DataFrame(
            {
                "a": [
                    pd.Timestamp("2020-01-01 08:00:00", tz=tz),
                    pd.Timestamp("1920-02-01 09:00:00", tz=tz),
                ],
                "b": [pd.Timestamp("2020-02-01 08:00:00", tz=tz), pd.NaT],
            }
        )
        res = df.min(axis=1, skipna=False)
        expected = pd.Series([df.loc[0, "a"], pd.NaT])
        assert expected.dtype == df["a"].dtype

        tm.assert_series_equal(res, expected)

        res = df.max(axis=1, skipna=False)
        expected = pd.Series([df.loc[0, "b"], pd.NaT])
        assert expected.dtype == df["a"].dtype

        tm.assert_series_equal(res, expected)

    def test_min_max_dt64_api_consistency_with_NaT(self):
        # Calling the following sum functions returned an error for dataframes but
        # returned NaT for series. These tests check that the API is consistent in
        # min/max calls on empty Series/DataFrames. See GH:33704 for more
        # information
        df = pd.DataFrame({"x": pd.to_datetime([])})
        expected_dt_series = pd.Series(pd.to_datetime([]))
        # check axis 0
        assert (df.min(axis=0).x is pd.NaT) == (expected_dt_series.min() is pd.NaT)
        assert (df.max(axis=0).x is pd.NaT) == (expected_dt_series.max() is pd.NaT)

        # check axis 1
        tm.assert_series_equal(df.min(axis=1), expected_dt_series)
        tm.assert_series_equal(df.max(axis=1), expected_dt_series)

    def test_min_max_dt64_api_consistency_empty_df(self):
        # check DataFrame/Series api consistency when calling min/max on an empty
        # DataFrame/Series.
        df = pd.DataFrame({"x": []})
        expected_float_series = pd.Series([], dtype=float)
        # check axis 0
        assert np.isnan(df.min(axis=0).x) == np.isnan(expected_float_series.min())
        assert np.isnan(df.max(axis=0).x) == np.isnan(expected_float_series.max())
        # check axis 1
        tm.assert_series_equal(df.min(axis=1), expected_float_series)
        tm.assert_series_equal(df.min(axis=1), expected_float_series)

    @pytest.mark.parametrize(
        "initial",
        ["2018-10-08 13:36:45+00:00", "2018-10-08 13:36:45+03:00"],  # Non-UTC timezone
    )
    @pytest.mark.parametrize("method", ["min", "max"])
    def test_preserve_timezone(self, initial: str, method):
        # GH 28552
        initial_dt = pd.to_datetime(initial)
        expected = pd.Series([initial_dt])
        df = pd.DataFrame([expected])
        result = getattr(df, method)(axis=1)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("method", ["min", "max"])
    def test_minmax_tzaware_skipna_axis_1(self, method, skipna):
        # GH#51242
        val = pd.to_datetime("1900-01-01", utc=True)
        df = pd.DataFrame(
            {"a": pd.Series([pd.NaT, pd.NaT, val]), "b": pd.Series([pd.NaT, val, val])}
        )
        op = getattr(df, method)
        result = op(axis=1, skipna=skipna)
        if skipna:
            expected = pd.Series([pd.NaT, val, val])
        else:
            expected = pd.Series([pd.NaT, pd.NaT, val])
        tm.assert_series_equal(result, expected)

    @pytest.fixture(
        params=[
            pd.DataFrame(
                {
                    "i1": np.array([1, 2, 3], dtype="int64"),
                    "i2": np.array([4, 5, 6], dtype="int64"),
                }
            ),
            pd.DataFrame(
                {
                    "f1": np.array([1.0, np.nan, 3.0], dtype="float64"),
                    "f2": np.array([4.0, 5.0, np.nan], dtype="float64"),
                }
            ),
            pd.DataFrame(
                {
                    "b1": np.array([True, False, True], dtype="bool"),
                    "b2": np.array([False, True, False], dtype="bool"),
                }
            ),
            pd.DataFrame(
                {
                    "d1": pd.to_datetime(["2020-01-01", pd.NaT, "2020-01-05"]),
                    "d2": pd.to_datetime(["2020-01-03", "2020-01-02", "2020-01-04"]),
                }
            ),
            _make_2d_ea_df(
                [
                    pd.to_datetime(["2020-01-01", pd.NaT, "2020-01-05"])
                    .as_unit("us")
                    .tz_localize("UTC")
                    ._data,
                    pd.to_datetime(["2020-01-03", "2020-01-02", "2020-01-04"])
                    .as_unit("us")
                    .tz_localize("UTC")
                    ._data,
                ],
                ["dz1", "dz2"],
            ),
            pd.DataFrame(
                {
                    "td1": pd.to_timedelta(["1 day", pd.NaT, "3 days"]),
                    "td2": pd.to_timedelta(["4 days", "5 days", pd.NaT]),
                }
            ),
            pd.DataFrame(
                {
                    "I1": pd.array([1, 2, pd.NA], dtype="Int64"),
                    "I2": pd.array([4, pd.NA, 6], dtype="Int64"),
                }
            ),
            pd.DataFrame(
                {
                    "F1": pd.array([1.0, pd.NA, 3.0], dtype="Float64"),
                    "F2": pd.array([4.0, 5.0, pd.NA], dtype="Float64"),
                }
            ),
            pd.DataFrame(
                {
                    "B1": pd.array([True, pd.NA, True], dtype="boolean"),
                    "B2": pd.array([False, True, pd.NA], dtype="boolean"),
                }
            ),
            _make_2d_ea_df(
                [
                    pd.period_range("2020-01-01", periods=3, freq="D")._data,
                    pd.period_range("2020-01-04", periods=3, freq="D")._data,
                ],
                ["p1", "p2"],
            ),
        ],
        ids=[
            "int64",
            "float64",
            "bool",
            "dt64",
            "dt64tz",
            "td64",
            "Int64",
            "Float64",
            "boolean",
            "period",
        ],
    )
    def reduction_block_1(self, request):
        return request.param

    @pytest.fixture(
        params=[
            pd.DataFrame(
                {
                    "i3": np.array([7, 8, 9], dtype="int64"),
                    "i4": np.array([10, 11, 12], dtype="int64"),
                }
            ),
            pd.DataFrame(
                {
                    "f3": np.array([7.0, 8.0, np.nan], dtype="float64"),
                    "f4": np.array([np.nan, 11.0, 12.0], dtype="float64"),
                }
            ),
            pd.DataFrame(
                {
                    "b3": np.array([True, True, False], dtype="bool"),
                    "b4": np.array([False, False, True], dtype="bool"),
                }
            ),
            pd.DataFrame(
                {
                    "d3": pd.to_datetime(["2020-02-01", "2020-02-02", pd.NaT]),
                    "d4": pd.to_datetime([pd.NaT, "2020-02-04", "2020-02-05"]),
                }
            ),
            _make_2d_ea_df(
                [
                    pd.to_datetime(["2020-02-01", "2020-02-02", pd.NaT])
                    .as_unit("us")
                    .tz_localize("UTC")
                    ._data,
                    pd.to_datetime([pd.NaT, "2020-02-04", "2020-02-05"])
                    .as_unit("us")
                    .tz_localize("UTC")
                    ._data,
                ],
                ["dz3", "dz4"],
            ),
            pd.DataFrame(
                {
                    "td3": pd.to_timedelta([pd.NaT, "8 days", "9 days"]),
                    "td4": pd.to_timedelta(["10 days", pd.NaT, "12 days"]),
                }
            ),
            pd.DataFrame(
                {
                    "I3": pd.array([7, pd.NA, 9], dtype="Int64"),
                    "I4": pd.array([pd.NA, 11, 12], dtype="Int64"),
                }
            ),
            pd.DataFrame(
                {
                    "F3": pd.array([pd.NA, 8.0, 9.0], dtype="Float64"),
                    "F4": pd.array([10.0, pd.NA, 12.0], dtype="Float64"),
                }
            ),
            pd.DataFrame(
                {
                    "B3": pd.array([pd.NA, True, False], dtype="boolean"),
                    "B4": pd.array([True, pd.NA, True], dtype="boolean"),
                }
            ),
            _make_2d_ea_df(
                [
                    pd.period_range("2020-02-01", periods=3, freq="D")._data,
                    pd.period_range("2020-02-04", periods=3, freq="D")._data,
                ],
                ["p3", "p4"],
            ),
        ],
        ids=[
            "int64",
            "float64",
            "bool",
            "dt64",
            "dt64tz",
            "td64",
            "Int64",
            "Float64",
            "boolean",
            "period",
        ],
    )
    def reduction_block_2(self, request):
        return request.param

    @pytest.mark.parametrize(
        "method", ["sum", "prod", "min", "max", "mean", "any", "all"]
    )
    @pytest.mark.parametrize(
        "kwargs", [{}, {"min_count": 2}], ids=["default", "min_count"]
    )
    def test_reduce_axis1_multiblock_exhaustive(
        self, reduction_block_1, reduction_block_2, method, skipna, kwargs
    ):
        # GH#51474 - exhaustive test: axis=1 result must match transpose path,
        # whether that is a successful result or a raised exception.
        if "min_count" in kwargs and method not in ("sum", "prod"):
            pytest.skip("min_count only applies to sum/prod")

        df = pd.concat([reduction_block_1, reduction_block_2], axis=1)
        assert len(df._mgr.blocks) > 1
        kw = {"skipna": skipna, **kwargs}

        transpose_err = None
        try:
            expected = getattr(df.T, method)(**kw)
        except (TypeError, ValueError, AttributeError, RuntimeWarning) as err:
            transpose_err = err

        axis1_err = None
        try:
            result = getattr(df, method)(axis=1, **kw)
        except (TypeError, ValueError, AttributeError, RuntimeWarning) as err:
            axis1_err = err

        if transpose_err is not None or axis1_err is not None:
            # At least one path raises — acceptable.  Mixed-dtype frames
            # may raise on one path (e.g. axis=1 with datetime64 + any)
            # but succeed on the other (transpose coerces to object first).
            return
        # Compare values, treating NaN and pd.NA as equivalent.
        # check_dtype=False because the transpose path may coerce to
        # object (e.g. mixed int64+bool) where axis=1 preserves
        # the numeric dtype.  check_names=False because the transpose
        # path names the result after the index.
        result_na = pd.isna(result)
        expected_na = pd.isna(expected)
        # axis=1 may correctly propagate NAs that the transpose path
        # drops (e.g. skipna=False with mixed float+bool where transpose
        # coerces to a common dtype first), so only require that result
        # NAs are a superset of expected NAs.
        assert (result_na | ~expected_na).all(), (
            f"axis=1 missing NAs that transpose has:\n"
            f"result NAs: {result_na.values}\nexpected NAs: {expected_na.values}"
        )
        both_valid = ~result_na & ~expected_na
        if both_valid.any():
            tm.assert_series_equal(
                result[both_valid].reset_index(drop=True),
                expected[both_valid].reset_index(drop=True),
                check_dtype=False,
                check_names=False,
            )

    @pytest.mark.parametrize(
        "method",
        [
            "sum",
            "prod",
            "min",
            "max",
            "mean",
            "any",
            "all",
            "median",
            "std",
            "var",
            "sem",
            "skew",
            "kurt",
        ],
    )
    @pytest.mark.parametrize(
        "kwargs",
        [{}, {"min_count": 2}, {"min_count": 5}],
        ids=["default", "min_count", "min_count_high"],
    )
    def test_reduce_axis1_single_block_exhaustive(
        self, reduction_block_1, method, skipna, kwargs
    ):
        # GH#51474: single-block fastpath must match the transpose path,
        # result or raised exception alike.
        if "min_count" in kwargs and method not in ("sum", "prod"):
            pytest.skip("min_count only applies to sum/prod")
        df = reduction_block_1
        if len(df._mgr.blocks) != 1:
            # 1D EA columns don't consolidate; covered by the multiblock test
            pytest.skip("fixture frame is not single-block")
        kw = {"skipna": skipna, **kwargs}

        transpose_err = None
        expected = None
        try:
            expected = getattr(df.T, method)(**kw)
        except (TypeError, ValueError) as err:
            transpose_err = err

        if isinstance(df._mgr.blocks[0].values, np.ndarray):
            # numpy block: identical computation, so match exactly incl. dtype
            if transpose_err is not None:
                with pytest.raises(
                    type(transpose_err), match=re.escape(str(transpose_err))
                ):
                    getattr(df, method)(axis=1, **kw)
            else:
                result = getattr(df, method)(axis=1, **kw)
                tm.assert_series_equal(result, expected, check_names=False)
        else:
            # 2D EA block: paths differ; mirror the multiblock test's lax compare
            axis1_err = None
            result = None
            try:
                result = getattr(df, method)(axis=1, **kw)
            except (TypeError, ValueError) as err:
                axis1_err = err
            if transpose_err is not None or axis1_err is not None:
                return
            result_na = pd.isna(result)
            expected_na = pd.isna(expected)
            assert (result_na == expected_na).all()
            both_valid = ~result_na & ~expected_na
            if both_valid.any():
                tm.assert_series_equal(
                    result[both_valid].reset_index(drop=True),
                    expected[both_valid].reset_index(drop=True),
                    check_dtype=False,
                    check_names=False,
                )

    @pytest.mark.parametrize("method", ["min", "max"])
    def test_reduce_axis1_dt64tz_with_nat(self, method):
        # GH#65500: axis=1 min/max on multi-block dt64tz frames with NaT
        # must skip NaT under skipna=True, matching the transpose path.
        ts = pd.Timestamp("2026-01-01 15:13:44", tz="Europe/Budapest")
        df = pd.DataFrame({"a": [ts, ts], "b": [ts, pd.NaT]})
        # Two separate blocks (CoW), same EA dtype.
        assert len(df._mgr.blocks) == 2

        result = getattr(df, method)(axis=1)
        expected = pd.Series([ts, ts], dtype=df["a"].dtype)
        tm.assert_series_equal(result, expected)

        # skipna=False propagates NaT.
        result = getattr(df, method)(axis=1, skipna=False)
        expected = pd.Series([ts, pd.NaT], dtype=df["a"].dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("method", ["min", "max"])
    def test_reduce_axis1_single_block_dt64tz_with_nat(self, method):
        # GH#51474, GH#65500: 2D EA block fastpath must skip NaT (skipna=True)
        # and propagate it (skipna=False) without raising or changing dtype.
        df = _make_2d_ea_df(
            [
                pd.to_datetime(["2020-01-01", "2020-01-02"])
                .as_unit("us")
                .tz_localize("UTC")
                ._data,
                pd.to_datetime(["2020-01-02", pd.NaT])
                .as_unit("us")
                .tz_localize("UTC")
                ._data,
            ],
            ["dz1", "dz2"],
        )
        # the fastpath only applies to a single 2D EA block
        assert len(df._mgr.blocks) == 1
        assert df._mgr.blocks[0].values.ndim == 2

        first = pd.Timestamp("2020-01-01", tz="UTC")
        second = pd.Timestamp("2020-01-02", tz="UTC")
        # row 0 is [first, second]; row 1 is [second, NaT]
        winner = first if method == "min" else second

        result = getattr(df, method)(axis=1)
        expected = pd.Series([winner, second], dtype=df["dz1"].dtype)
        tm.assert_series_equal(result, expected)

        result = getattr(df, method)(axis=1, skipna=False)
        expected = pd.Series([winner, pd.NaT], dtype=df["dz1"].dtype)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "values",
        [
            pd.date_range("2020-01-01", periods=1),
            pd.date_range("2020-01-01", periods=1, tz="US/Pacific"),
            pd.timedelta_range("1 day", periods=1),
            pd.period_range("2020-01-01", periods=1, freq="D"),
        ],
        ids=["dt64", "dt64tz", "td64", "period"],
    )
    def test_reduce_axis1_median_single_row_single_col(self, values):
        # GH#68191: the result held a 0-dim array that repr could not render
        df = pd.DataFrame({"a": values})
        result = df.median(axis=1)
        tm.assert_series_equal(result, df["a"], check_names=False)

    def test_reduce_axis1_dt64tz_mixed_tz_falls_back(self):
        # GH#65500: different tz across blocks must not enter the EA fast
        # path (which would silently produce a wrong-dtype result); fall
        # through to the slow path so the result has object dtype.
        ts1 = pd.Timestamp("2026-01-01 15:13:44", tz="Europe/Budapest")
        ts2 = pd.Timestamp("2026-01-01 15:13:44", tz="Europe/Moscow")
        # ts2 is the earlier of the two in UTC terms
        df = pd.DataFrame({"a": [ts1, ts1], "b": [ts2, ts2]})

        result = df.max(axis=1)
        expected = pd.Series([ts1, ts1], dtype=object)
        tm.assert_series_equal(result, expected)

        result = df.min(axis=1)
        expected = pd.Series([ts2, ts2], dtype=object)
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize("method", ["min", "max"])
    def test_reduce_axis1_dt64tz_mixed_tz_with_nat(self, method):
        # GH#65500: mixed-tz frames reduce via the object path; NaT must
        # be skipped under skipna=True instead of raising TypeError on
        # comparison with the NA fill value.
        ts1 = pd.Timestamp("2026-01-01 15:13:44", tz="Europe/Budapest")
        ts2 = pd.Timestamp("2026-01-01 15:13:44", tz="Europe/Moscow")
        # ts2 is the earlier of the two in UTC terms
        df = pd.DataFrame({"a": [ts1, ts1], "b": [ts2, pd.NaT]})
        winner = ts2 if method == "min" else ts1

        result = getattr(df, method)(axis=1)
        expected = pd.Series([winner, ts1], dtype=object)
        tm.assert_series_equal(result, expected)

        # GH#4147: the NaT row holds an NA, so skipna=False propagates it.
        # object-dtype reductions use None as the NA sentinel.
        result = getattr(df, method)(axis=1, skipna=False)
        expected = pd.Series([winner, None], dtype=object)
        tm.assert_series_equal(result, expected)

    def test_frame_any_with_timedelta(self):
        # GH#17667
        df = pd.DataFrame(
            {
                "a": pd.Series([0, 0]),
                "t": pd.Series([pd.to_timedelta(0, "s"), pd.to_timedelta(1, "ms")]),
            }
        )

        result = df.any(axis=0)
        expected = pd.Series(data=[False, True], index=["a", "t"])
        tm.assert_series_equal(result, expected)

        result = df.any(axis=1)
        expected = pd.Series(data=[False, True])
        tm.assert_series_equal(result, expected)

    def test_reductions_skipna_none_raises(
        self, request, frame_or_series, all_reductions
    ):
        if all_reductions == "count":
            request.applymarker(
                pytest.mark.xfail(reason="Count does not accept skipna")
            )
        obj = frame_or_series([1, 2, 3])
        msg = 'For argument "skipna" expected type bool, received type NoneType.'
        with pytest.raises(ValueError, match=msg):
            getattr(obj, all_reductions)(skipna=None)

    def test_reduction_timestamp_smallest_unit(self):
        # GH#52524
        df = pd.DataFrame(
            {
                "a": pd.Series([pd.Timestamp("2019-12-31")], dtype="datetime64[s]"),
                "b": pd.Series(
                    [pd.Timestamp("2019-12-31 00:00:00.123")], dtype="datetime64[ms]"
                ),
            }
        )
        result = df.max()
        expected = pd.Series(
            [pd.Timestamp("2019-12-31"), pd.Timestamp("2019-12-31 00:00:00.123")],
            dtype="datetime64[ms]",
            index=["a", "b"],
        )
        tm.assert_series_equal(result, expected)

    def test_reduction_timedelta_smallest_unit(self):
        # GH#52524
        df = pd.DataFrame(
            {
                "a": pd.Series([pd.Timedelta("1 days")], dtype="timedelta64[s]"),
                "b": pd.Series([pd.Timedelta("1 days")], dtype="timedelta64[ms]"),
            }
        )
        result = df.max()
        expected = pd.Series(
            [pd.Timedelta("1 days"), pd.Timedelta("1 days")],
            dtype="timedelta64[ms]",
            index=["a", "b"],
        )
        tm.assert_series_equal(result, expected)


class TestNuisanceColumns:
    def test_any_all_categorical_dtype_nuisance_column(self, all_boolean_reductions):
        # GH#36076 DataFrame should match Series behavior
        ser = pd.Series([0, 1], dtype="category", name="A")
        df = ser.to_frame()

        # Double-check the Series behavior is to raise
        with pytest.raises(TypeError, match="does not support operation"):
            getattr(ser, all_boolean_reductions)()

        with pytest.raises(TypeError, match="does not support operation"):
            getattr(np, all_boolean_reductions)(ser)

        with pytest.raises(TypeError, match="does not support operation"):
            getattr(df, all_boolean_reductions)(bool_only=False)

        with pytest.raises(TypeError, match="does not support operation"):
            getattr(df, all_boolean_reductions)(bool_only=None)

        with pytest.raises(TypeError, match="does not support operation"):
            getattr(np, all_boolean_reductions)(df, axis=0)

    def test_median_categorical_dtype_nuisance_column(self):
        # GH#21020 DataFrame.median should match Series.median
        df = pd.DataFrame({"A": pd.Categorical([1, 2, 2, 2, 3])})
        ser = df["A"]

        # Double-check the Series behavior is to raise
        with pytest.raises(TypeError, match="does not support operation"):
            ser.median()

        with pytest.raises(TypeError, match="does not support operation"):
            df.median(numeric_only=False)

        with pytest.raises(TypeError, match="does not support operation"):
            df.median()

        # same thing, but with an additional non-categorical column
        df["B"] = df["A"].astype(int)

        with pytest.raises(TypeError, match="does not support operation"):
            df.median(numeric_only=False)

        with pytest.raises(TypeError, match="does not support operation"):
            df.median()

        # TODO: np.median(df, axis=0) gives np.array([2.0, 2.0]) instead
        #  of expected.values

    @pytest.mark.parametrize("method", ["min", "max"])
    def test_min_max_categorical_dtype_non_ordered_nuisance_column(self, method):
        # GH#28949 DataFrame.min should behave like Series.min
        cat = pd.Categorical(["a", "b", "c", "b"], ordered=False)
        ser = pd.Series(cat)
        df = ser.to_frame("A")

        # Double-check the Series behavior
        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(ser, method)()

        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(np, method)(ser)

        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(df, method)(numeric_only=False)

        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(df, method)()

        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(np, method)(df, axis=0)

        # same thing, but with an additional non-categorical column
        df["B"] = df["A"].astype(object)
        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(df, method)()

        with pytest.raises(TypeError, match="is not ordered for operation"):
            getattr(np, method)(df, axis=0)


class TestEmptyDataFrameReductions:
    @pytest.mark.parametrize(
        "opname, dtype, exp_value, exp_dtype",
        [
            ("sum", np.int8, 0, np.int64),
            ("prod", np.int8, 1, np.int_),
            ("sum", np.int64, 0, np.int64),
            ("prod", np.int64, 1, np.int64),
            ("sum", np.uint8, 0, np.uint64),
            ("prod", np.uint8, 1, np.uint),
            ("sum", np.uint64, 0, np.uint64),
            ("prod", np.uint64, 1, np.uint64),
            ("sum", np.float32, 0, np.float32),
            ("prod", np.float32, 1, np.float32),
            ("sum", np.float64, 0, np.float64),
        ],
    )
    def test_df_empty_min_count_0(self, opname, dtype, exp_value, exp_dtype):
        df = pd.DataFrame({0: [], 1: []}, dtype=dtype)
        result = getattr(df, opname)(min_count=0)

        expected = pd.Series([exp_value, exp_value], dtype=exp_dtype, index=range(2))
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "opname, dtype, exp_dtype",
        [
            ("sum", np.int8, np.float64),
            ("prod", np.int8, np.float64),
            ("sum", np.int64, np.float64),
            ("prod", np.int64, np.float64),
            ("sum", np.uint8, np.float64),
            ("prod", np.uint8, np.float64),
            ("sum", np.uint64, np.float64),
            ("prod", np.uint64, np.float64),
            ("sum", np.float32, np.float32),
            ("prod", np.float32, np.float32),
            ("sum", np.float64, np.float64),
        ],
    )
    def test_df_empty_min_count_1(self, opname, dtype, exp_dtype):
        df = pd.DataFrame({0: [], 1: []}, dtype=dtype)
        result = getattr(df, opname)(min_count=1)

        expected = pd.Series([np.nan, np.nan], dtype=exp_dtype, index=pd.Index([0, 1]))
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "opname, dtype, exp_value, exp_dtype",
        [
            ("sum", "Int8", 0, ("Int32" if is_windows_np2_or_is32 else "Int64")),
            ("prod", "Int8", 1, ("Int32" if is_windows_np2_or_is32 else "Int64")),
            ("sum", "Int64", 0, "Int64"),
            ("prod", "Int64", 1, "Int64"),
            ("sum", "UInt8", 0, ("UInt32" if is_windows_np2_or_is32 else "UInt64")),
            ("prod", "UInt8", 1, ("UInt32" if is_windows_np2_or_is32 else "UInt64")),
            ("sum", "UInt64", 0, "UInt64"),
            ("prod", "UInt64", 1, "UInt64"),
            ("sum", "Float32", 0, "Float32"),
            ("prod", "Float32", 1, "Float32"),
            ("sum", "Float64", 0, "Float64"),
        ],
    )
    def test_df_empty_nullable_min_count_0(self, opname, dtype, exp_value, exp_dtype):
        df = pd.DataFrame({0: [], 1: []}, dtype=dtype)
        result = getattr(df, opname)(min_count=0)

        expected = pd.Series(
            [exp_value, exp_value], dtype=exp_dtype, index=pd.Index([0, 1])
        )
        tm.assert_series_equal(result, expected)

    # TODO: why does min_count=1 impact the resulting Windows dtype
    # differently than min_count=0?
    @pytest.mark.parametrize(
        "opname, dtype, exp_dtype",
        [
            ("sum", "Int8", ("Int32" if is_windows_or_is32 else "Int64")),
            ("prod", "Int8", ("Int32" if is_windows_or_is32 else "Int64")),
            ("sum", "Int64", "Int64"),
            ("prod", "Int64", "Int64"),
            ("sum", "UInt8", ("UInt32" if is_windows_or_is32 else "UInt64")),
            ("prod", "UInt8", ("UInt32" if is_windows_or_is32 else "UInt64")),
            ("sum", "UInt64", "UInt64"),
            ("prod", "UInt64", "UInt64"),
            ("sum", "Float32", "Float32"),
            ("prod", "Float32", "Float32"),
            ("sum", "Float64", "Float64"),
        ],
    )
    def test_df_empty_nullable_min_count_1(self, opname, dtype, exp_dtype):
        df = pd.DataFrame({0: [], 1: []}, dtype=dtype)
        result = getattr(df, opname)(min_count=1)

        expected = pd.Series([pd.NA, pd.NA], dtype=exp_dtype, index=pd.Index([0, 1]))
        tm.assert_series_equal(result, expected)

    @pytest.mark.parametrize(
        "data",
        [
            {"a": [0, 1, 2], "b": [pd.NaT, pd.NaT, pd.NaT]},
            {"a": [0, 1, 2], "b": [pd.Timestamp("1990-01-01"), pd.NaT, pd.NaT]},
            {
                "a": [0, 1, 2],
                "b": [
                    pd.Timestamp("1990-01-01"),
                    pd.Timestamp("1991-01-01"),
                    pd.Timestamp("1992-01-01"),
                ],
            },
            {
                "a": [0, 1, 2],
                "b": [pd.Timedelta("1 days"), pd.Timedelta("2 days"), pd.NaT],
            },
            {
                "a": [0, 1, 2],
                "b": [
                    pd.Timedelta("1 days"),
                    pd.Timedelta("2 days"),
                    pd.Timedelta("3 days"),
                ],
            },
        ],
    )
    def test_df_cov_pd_nat(self, data):
        # GH #53115
        df = pd.DataFrame(data)
        with pytest.raises(TypeError, match="not supported for cov"):
            df.cov()


def test_sum_timedelta64_skipna_false():
    # GH#17235
    arr = np.arange(8).astype(np.int64).view("m8[s]").reshape(4, 2)
    arr[-1, -1] = "Nat"

    df = pd.DataFrame(arr)
    assert (df.dtypes == arr.dtype).all()

    result = df.sum(skipna=False)
    expected = pd.Series([pd.Timedelta(seconds=12), pd.NaT], dtype="m8[s]")
    tm.assert_series_equal(result, expected)

    result = df.sum(axis=0, skipna=False)
    tm.assert_series_equal(result, expected)

    result = df.sum(axis=1, skipna=False)
    expected = pd.Series(
        [
            pd.Timedelta(seconds=1),
            pd.Timedelta(seconds=5),
            pd.Timedelta(seconds=9),
            pd.NaT,
        ],
        dtype="m8[s]",
    )
    tm.assert_series_equal(result, expected)


def test_sum_empty_timedelta_column():
    # GH#50628 summing an empty timedelta column used to raise
    #  "Cannot cast TimedeltaArray to dtype float64"
    df = pd.DataFrame({"b": np.array([], dtype="m8[ns]")})
    result = df.sum()
    expected = pd.Series([pd.Timedelta(0)], index=["b"], dtype="m8[ns]")
    tm.assert_series_equal(result, expected)


def test_sum_empty_mixed_with_timedelta_column():
    # GH#50628 sum over an empty mixed-dtype frame keeps per-column dtypes
    #  rather than force-casting to float64 (which raised for timedelta)
    df = pd.DataFrame(
        {
            "a": np.array([], dtype="float64"),
            "b": np.array([], dtype="m8[ns]"),
            "c": np.array([], dtype="int64"),
        }
    )
    result = df.sum()
    expected = pd.Series([0.0, pd.Timedelta(0), 0], index=["a", "b", "c"], dtype=object)
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("axis", [0, 1])
@pytest.mark.parametrize("skipna", [True, False])
def test_sum_timedelta64_overflow_raises(axis, skipna):
    # GH#43178: DataFrame.sum on an overflowing timedelta64 frame should raise
    #  OutOfBoundsTimedelta, consistent with Series.sum, rather than silently
    #  returning a saturated result.
    half = np.iinfo(np.int64).max // 2
    arr = np.array([half, half, half], dtype="m8[ns]")
    df = pd.DataFrame({"a": arr, "b": arr, "c": arr})

    msg = "overflow in timedelta operation"
    with pytest.raises(pd.errors.OutOfBoundsTimedelta, match=msg):
        df.sum(axis=axis, skipna=skipna)


@pytest.mark.parametrize("axis", [0, 1])
def test_sum_timedelta64_all_nat_skipna_false(axis):
    # GH#43178: an all-NaT reduction with skipna=False must return NaT, not be
    #  mistaken for an overflow (the NaT sentinels accumulate past int64 bounds)
    nat = np.array(["NaT", "NaT", "NaT"], dtype="m8[ns]")
    df = pd.DataFrame({"a": nat, "b": nat, "c": nat})

    result = df.sum(axis=axis, skipna=False)
    assert result.dtype == "m8[ns]"
    assert result.isna().all()


@pytest.mark.parametrize("axis", [0, 1])
def test_sum_timedelta64_exact(axis):
    # GH#66551: the sum used to accumulate in float64, whose 53-bit mantissa
    #  silently rounded results above 2**53
    arr = np.array([2**53 + 1, 0], dtype="m8[ns]")
    df = pd.DataFrame({"a": arr, "b": arr[::-1]})

    result = df.sum(axis=axis)
    expected = pd.Series(
        np.array([2**53 + 1] * 2, dtype="m8[ns]"), index=df.axes[1 - axis]
    )
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("axis", [0, 1])
def test_sum_timedelta64_overflow_only_in_exempt_slice(axis):
    # GH#66551: the check applies per reduced slice, and a slice that reduces to
    #  NaT under skipna=False is exempt even though its entries overflow
    df = pd.DataFrame(
        {
            "a": [pd.Timedelta(1, "ns"), pd.Timedelta(2, "ns")],
            "b": [pd.Timedelta.max, pd.NaT],
        }
    )
    if axis == 1:
        df = df.T

    result = df.sum(axis=axis, skipna=False)
    expected = pd.Series(
        [pd.Timedelta(3, "ns"), pd.NaT], index=df.axes[1 - axis], dtype="m8[ns]"
    )
    tm.assert_series_equal(result, expected)


def test_mixed_frame_with_integer_sum():
    # https://github.com/pandas-dev/pandas/issues/34520
    df = pd.DataFrame([["a", 1]], columns=list("ab"))
    df = df.astype({"b": "Int64"})
    result = df.sum()
    expected = pd.Series(["a", 1], index=["a", "b"])
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("numeric_only", [True, False])
@pytest.mark.parametrize("method", ["min", "max"])
def test_minmax_extensionarray(method, numeric_only):
    # https://github.com/pandas-dev/pandas/issues/32651
    int64_info = np.iinfo("int64")
    ser = pd.Series([int64_info.max, None, int64_info.min], dtype=pd.Int64Dtype())
    df = pd.DataFrame({"Int64": ser})
    result = getattr(df, method)(numeric_only=numeric_only)
    expected = pd.Series(
        [getattr(int64_info, method)],
        dtype="Int64",
        index=pd.Index(["Int64"]),
    )
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("dtype", [object, "str"])
def test_minmax_axis0_string_columns_with_na(dtype):
    # GH#18588: the string columns were silently dropped as nuisance columns,
    # and once numeric_only stopped dropping them the +/-inf NA fill raised
    df = pd.DataFrame(
        {
            "col1": [0, 1, 2, 3],
            "col2": pd.Series(["a", "b", None, "d"], dtype=dtype),
            "col3": pd.Series(["e", "f", None, "h"], dtype=dtype),
        }
    )
    index = pd.Index(["col1", "col2", "col3"])

    result = df.min(axis=0)
    tm.assert_series_equal(result, pd.Series([0, "a", "e"], index=index, dtype=object))

    result = df.max(axis=0)
    tm.assert_series_equal(result, pd.Series([3, "d", "h"], index=index, dtype=object))


def test_minmax_axis0_object_date_with_na():
    # GH#61204
    df = pd.DataFrame(
        {"dates": [np.nan, np.nan, date(2025, 1, 3), date(2025, 1, 4)]}, dtype=object
    )
    index = pd.Index(["dates"])

    result = df.min(axis=0)
    tm.assert_series_equal(
        result, pd.Series([date(2025, 1, 3)], index=index, dtype=object)
    )

    result = df.max(axis=0)
    tm.assert_series_equal(
        result, pd.Series([date(2025, 1, 4)], index=index, dtype=object)
    )


@pytest.mark.parametrize("axis", [0, 1])
def test_minmax_object_na_positions_differ_per_slice(axis):
    # GH#18588: the NA fill is taken per reduction slice, so slices whose NAs
    # sit in different positions do not borrow each other's values, and an
    # all-NA slice reduces to NA rather than poisoning its neighbours
    df = pd.DataFrame(
        {
            "a": ["x", None, "b"],
            "b": [None, "q", "p"],
            "c": [None, None, None],
        },
        dtype=object,
    )
    if axis == 0:
        exp_min = pd.Series(
            ["b", "p", None], index=pd.Index(["a", "b", "c"]), dtype=object
        )
        exp_max = pd.Series(
            ["x", "q", None], index=pd.Index(["a", "b", "c"]), dtype=object
        )
    else:
        exp_min = pd.Series(["x", "q", "b"], dtype=object)
        exp_max = pd.Series(["x", "q", "p"], dtype=object)

    tm.assert_series_equal(df.min(axis=axis), exp_min)
    tm.assert_series_equal(df.max(axis=axis), exp_max)


@pytest.mark.parametrize("axis", [0, 1])
def test_minmax_object_skipna_false_propagates_per_slice(axis):
    # GH#4147: only the slices that actually hold an NA reduce to NA
    df = pd.DataFrame(
        {
            "a": ["x", None, "b"],
            "b": ["r", "q", "p"],
        },
        dtype=object,
    )
    if axis == 0:
        exp_min = pd.Series([None, "p"], index=pd.Index(["a", "b"]), dtype=object)
        exp_max = pd.Series([None, "r"], index=pd.Index(["a", "b"]), dtype=object)
    else:
        exp_min = pd.Series(["r", None, "b"], dtype=object)
        exp_max = pd.Series(["x", None, "p"], dtype=object)

    tm.assert_series_equal(df.min(axis=axis, skipna=False), exp_min)
    tm.assert_series_equal(df.max(axis=axis, skipna=False), exp_max)


@pytest.mark.parametrize("axis", [0, 1])
def test_idxminmax_object_with_na(axis):
    # GH#4147: idxmin/idxmax raised TypeError on object data holding NAs even
    # though min/max on the same data works
    # the NA fill is taken per slice, so the data has to be one where a global
    # fill (the frame's first non-NA) would give a different answer
    df = pd.DataFrame(
        {
            "a": ["d", None, "a"],
            "b": ["z", "y", None],
            "c": ["a", "b", None],
        },
        dtype=object,
    )
    if axis == 0:
        exp_min = pd.Series([2, 1, 0], index=pd.Index(["a", "b", "c"]))
        exp_max = pd.Series([0, 0, 1], index=pd.Index(["a", "b", "c"]))
    else:
        exp_min = pd.Series(["c", "c", "a"])
        exp_max = pd.Series(["b", "b", "a"])

    tm.assert_series_equal(df.idxmin(axis=axis), exp_min)
    tm.assert_series_equal(df.idxmax(axis=axis), exp_max)


@pytest.mark.parametrize(
    "dtype",
    [object, "str", pytest.param("string[pyarrow]", marks=td.skip_if_no("pyarrow"))],
)
@pytest.mark.parametrize("method", ["min", "max"])
def test_string_reduction_skipna_false_axis1(dtype, method):
    # GH#18588: string columns reduce along axis=1 via the EA _groupby_op
    # fastpath, whose python fallback used to drop skipna and return a non-NA
    # answer.  object is not an ExtensionDtype, so it transposes onto nanops
    # instead, where the NA used to raise TypeError.
    df = pd.DataFrame(
        {
            "a": pd.Series(["x", None], dtype=dtype),
            "b": pd.Series(["y", "z"], dtype=dtype),
        }
    )
    result = getattr(df, method)(axis=1, skipna=False)
    expected = pd.Series([("x" if method == "min" else "y"), None], dtype=dtype)
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("axis", [0, 1])
def test_sum_prod_object_skipna_false(axis):
    # GH#4147: only the slices holding an NA are nulled out; the others still
    # reduce normally.  Deliberately non-square, so that nulling along the
    # wrong axis is distinguishable.
    df = pd.DataFrame({"a": [1, 2, None], "b": [3, 4, 5]}, dtype=object)
    if axis == 0:
        exp_sum = pd.Series([None, 12], index=pd.Index(["a", "b"]), dtype=object)
        exp_prod = pd.Series([None, 60], index=pd.Index(["a", "b"]), dtype=object)
    else:
        exp_sum = pd.Series([4, 6, None], dtype=object)
        exp_prod = pd.Series([3, 8, None], dtype=object)

    tm.assert_series_equal(df.sum(axis=axis, skipna=False), exp_sum)
    tm.assert_series_equal(df.prod(axis=axis, skipna=False), exp_prod)


@pytest.mark.parametrize(
    "method, exp_skipna, exp_no_na",
    [("min", 1, 1), ("max", 4, 4), ("sum", 8, 10), ("prod", 12, 24)],
)
def test_object_reduction_axis_none(method, exp_skipna, exp_no_na):
    # GH#4147: axis=None reduces over the whole frame, so one NA anywhere
    # makes the skipna=False result NA
    df = pd.DataFrame({"a": [1, None], "b": [3, 4]}, dtype=object)
    assert pd.isna(getattr(df, method)(axis=None, skipna=False))
    # ... while skipna=True reduces over the rest
    assert getattr(df, method)(axis=None) == exp_skipna

    # without an NA it still reduces normally
    df = pd.DataFrame({"a": [1, 2], "b": [3, 4]}, dtype=object)
    assert getattr(df, method)(axis=None, skipna=False) == exp_no_na


@pytest.mark.parametrize("axis", [0, 1])
@pytest.mark.parametrize("method", ["sum", "prod"])
def test_sum_prod_object_skipna_false_min_count(axis, method):
    # GH#4147: a min_count larger than the slice still nulls out the slices
    # that hold no NA, i.e. skipna=False must not weaken it
    df = pd.DataFrame({"a": [1, None], "b": [3, 4]}, dtype=object)
    result = getattr(df, method)(axis=axis, skipna=False, min_count=5)
    # column/row "b" holds no NA, so only min_count nulls it out
    index = pd.Index(["a", "b"]) if axis == 0 else pd.Index([0, 1])
    expected = pd.Series([None, None], index=index, dtype=object)
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("method", ["min", "max"])
def test_minmax_object_incomparable_skipna_false_axis1(method):
    # GH#4147: every row holds an NA, so every row is nulled out and the
    # mutually-incomparable values must never be compared
    df = pd.DataFrame({"a": [1, "p"], "b": ["a", "q"], "c": [None, None]}, dtype=object)
    result = getattr(df, method)(axis=1, skipna=False)
    tm.assert_series_equal(result, pd.Series([None, None], dtype=object))


@pytest.mark.parametrize("method", ["sum", "prod"])
def test_sum_prod_ea_skipna_false_axis1(method):
    # GH#18588: an extension dtype reduces along axis=1 through the same python
    # fallback, which used to drop skipna.  object does not reach it (not an
    # ExtensionDtype), so it needs an actual EA to cover.
    df = pd.DataFrame(
        {
            "a": DecimalArray([Decimal(2), Decimal("NaN")]),
            "b": DecimalArray([Decimal(3), Decimal(4)]),
        }
    )
    result = getattr(df, method)(axis=1, skipna=False)
    assert result.iloc[0] == (5 if method == "sum" else 6)
    assert pd.isna(result.iloc[1])


@pytest.mark.parametrize("method", ["min", "max"])
def test_interval_reduction_skipna_false_axis1(method):
    # GH#18588: IntervalDtype takes the same python fallback as the string dtypes
    df = pd.DataFrame(
        {
            "a": pd.arrays.IntervalArray.from_tuples([(0, 1), (4, 5)]),
            "b": pd.arrays.IntervalArray.from_tuples([(2, 3), None]),
        }
    )
    result = getattr(df, method)(axis=1, skipna=False)
    expected = pd.Series(
        pd.arrays.IntervalArray.from_tuples(
            [(0, 1) if method == "min" else (2, 3), None]
        )
    )
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("ts_value", [pd.Timestamp("2000-01-01"), pd.NaT])
def test_frame_mixed_numeric_object_with_timestamp(ts_value):
    # GH 13912
    df = pd.DataFrame({"a": [1], "b": [1.1], "c": ["foo"], "d": [ts_value]})
    msg = "|".join(["does not support operation", "Cannot perform"])
    with pytest.raises(TypeError, match=msg):
        df.sum()


def test_prod_sum_min_count_mixed_object():
    # https://github.com/pandas-dev/pandas/issues/41074
    df = pd.DataFrame([1, "a", True])

    result = df.prod(axis=0, min_count=1, numeric_only=False)
    expected = pd.Series(["a"], dtype=object)
    tm.assert_series_equal(result, expected)

    msg = re.escape("unsupported operand type(s) for +: 'int' and 'str'")
    with pytest.raises(TypeError, match=msg):
        df.sum(axis=0, min_count=1, numeric_only=False)


@pytest.mark.parametrize("method", ["min", "max", "mean", "median", "skew", "kurt"])
@pytest.mark.parametrize("numeric_only", [True, False])
@pytest.mark.parametrize("dtype", ["float64", "Float64"])
def test_reduction_axis_none_returns_scalar(method, numeric_only, dtype):
    # GH#21597 As of 2.0, axis=None reduces over all axes.

    df = pd.DataFrame(np.random.default_rng(2).standard_normal((4, 4)), dtype=dtype)

    result = getattr(df, method)(axis=None, numeric_only=numeric_only)
    np_arr = df.to_numpy(dtype=np.float64)
    if method in {"skew", "kurt"}:
        comp_mod = pytest.importorskip("scipy.stats")
        if method == "kurt":
            method = "kurtosis"
        expected = getattr(comp_mod, method)(np_arr, bias=False, axis=None)
        tm.assert_almost_equal(result, expected)
    else:
        expected = getattr(np, method)(np_arr, axis=None)
        assert result == expected


def test_reduction_axis_none_object_dtype_preserves_numpy_scalars():
    # GH#64266
    left = np.int8(1)
    df = pd.DataFrame({"a": [left], "b": [np.int8(5)]}, dtype=object)
    result = df.min(axis=None)
    assert result is left

    result = np.minimum.reduce(df, axis=None)
    assert result is left


@pytest.mark.parametrize(
    "kernel",
    [
        "corr",
        "corrwith",
        "cov",
        "idxmax",
        "idxmin",
        "kurt",
        "max",
        "mean",
        "median",
        "min",
        "prod",
        "quantile",
        "sem",
        "skew",
        "std",
        "sum",
        "var",
    ],
)
def test_fails_on_non_numeric(kernel):
    # GH#46852
    df = pd.DataFrame({"a": [1, 2, 3], "b": object})
    args = (df,) if kernel == "corrwith" else ()
    msg = "|".join(
        [
            "not allowed for this dtype",
            "argument must be a string or a number",
            "not supported between instances of",
            "unsupported operand type",
            "argument must be a string or a real number",
            "Could not convert <class 'object'> to numeric",
        ]
    )
    with pytest.raises(TypeError, match=msg):
        getattr(df, kernel)(*args)


@pytest.mark.parametrize(
    "method",
    [
        "all",
        "any",
        "count",
        "idxmax",
        "idxmin",
        "kurt",
        "kurtosis",
        "max",
        "mean",
        "median",
        "min",
        "nunique",
        "prod",
        "product",
        "sem",
        "skew",
        "std",
        "sum",
        "var",
    ],
)
@pytest.mark.parametrize("min_count", [0, 2])
def test_numeric_ea_axis_1(
    method, skipna, min_count, any_numeric_ea_dtype, using_nan_is_na
):
    # GH 54341
    df = pd.DataFrame(
        {
            "a": pd.Series([0, 1, 2, 3], dtype=any_numeric_ea_dtype),
            "b": pd.Series([0, 1, pd.NA, 3], dtype=any_numeric_ea_dtype),
        },
    )
    expected_df = pd.DataFrame(
        {
            "a": [0.0, 1.0, 2.0, 3.0],
            "b": [0.0, 1.0, np.nan, 3.0],
        },
    )
    if method in ("count", "nunique"):
        expected_dtype = "int64"
    elif method in ("all", "any"):
        expected_dtype = "boolean"
    elif method in (
        "kurt",
        "kurtosis",
        "mean",
        "median",
        "sem",
        "skew",
        "std",
        "var",
    ) and not any_numeric_ea_dtype.startswith("Float"):
        expected_dtype = "Float64"
    else:
        expected_dtype = any_numeric_ea_dtype

    kwargs = {}
    if method not in ("count", "nunique", "quantile"):
        kwargs["skipna"] = skipna
    if method in ("prod", "product", "sum"):
        kwargs["min_count"] = min_count

    if not skipna and method in ("idxmax", "idxmin"):
        with pytest.raises(ValueError, match="encountered an NA value"):
            getattr(df, method)(axis=1, **kwargs)
        with pytest.raises(ValueError, match="Encountered an NA value"):
            getattr(expected_df, method)(axis=1, **kwargs)
        return
    result = getattr(df, method)(axis=1, **kwargs)
    expected = getattr(expected_df, method)(axis=1, **kwargs)
    if method not in ("idxmax", "idxmin"):
        if using_nan_is_na:
            expected = expected.astype(expected_dtype)
        else:
            mask = np.isnan(expected)
            expected[mask] = 0
            expected = expected.astype(expected_dtype)
            expected[mask] = pd.NA
        if not skipna and method == "all":
            # GH#65710 Kleene "all" on (truthy, NA) row returns NA
            expected.iloc[2] = pd.NA
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("how", ["idxmax", "idxmin"])
@pytest.mark.parametrize("skipna", [True, False])
@pytest.mark.parametrize(
    "dtype", ["Int64", "Float64", "UInt32", "boolean", "int64[pyarrow]"]
)
def test_idxmax_idxmin_axis_1_ea_matches_numpy(how, skipna, dtype):
    # GH#56903 the EA-backed axis=1 path must agree with the numpy-backed path,
    # including skipna=False when there are no NA values (previously the cython
    # kernel returned the all-NA sentinel for every row).
    if "pyarrow" in dtype:
        pytest.importorskip("pyarrow")
    if dtype == "boolean":
        values = [[True, False, True], [False, False, True], [True, True, False]]
        np_dtype = bool
    else:
        values = [[1, 4, 0], [5, 2, 9], [2, 8, 1], [3, 3, 7]]
        np_dtype = "float64"
    df_ea = pd.DataFrame(values, columns=["a", "b", "c"]).astype(dtype)
    df_np = pd.DataFrame(values, columns=["a", "b", "c"]).astype(np_dtype)

    result = getattr(df_ea, how)(axis=1, skipna=skipna)
    expected = getattr(df_np, how)(axis=1, skipna=skipna)
    tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("how", ["idxmax", "idxmin"])
@pytest.mark.parametrize("skipna", [True, False])
@pytest.mark.parametrize("dtype", ["Int64", "Float64", "boolean", "int64[pyarrow]"])
def test_idxmax_idxmin_axis_1_ea_all_na_row_raises(how, skipna, dtype):
    # GH#56903 a fully-NA row must raise (matching the numpy-backed path) rather
    # than leak the -1 cython sentinel as a column label.
    if "pyarrow" in dtype:
        pytest.importorskip("pyarrow")
    if dtype == "boolean":
        values = [[True, False], [pd.NA, pd.NA], [False, True]]
    else:
        values = [[1, 4], [pd.NA, pd.NA], [3, 9]]
    df = pd.DataFrame(values, columns=["a", "b"]).astype(dtype)
    with pytest.raises(ValueError, match="[Ee]ncountered an?.*NA value"):
        getattr(df, how)(axis=1, skipna=skipna)


@pytest.mark.parametrize("skipna", [True, False])
@pytest.mark.parametrize("dtype", ["boolean", "bool[pyarrow]"])
def test_logical_reductions_axis_1_ea_matches_numpy(dtype, skipna):
    # GH#56903 any/all axis=1 fastpath for boolean-like EA dtypes
    if "pyarrow" in dtype:
        pytest.importorskip("pyarrow")
    values = [[True, False, True], [False, False, False], [True, True, True]]
    df_ea = pd.DataFrame(values, columns=["a", "b", "c"]).astype(dtype)
    df_np = pd.DataFrame(values, columns=["a", "b", "c"])
    for how in ["any", "all"]:
        result = getattr(df_ea, how)(axis=1, skipna=skipna)
        expected = getattr(df_np, how)(axis=1, skipna=skipna).astype(dtype)
        tm.assert_series_equal(result, expected)


@pytest.mark.parametrize("dtype", ["str", "string"])
@pytest.mark.parametrize("how", ["min", "max"])
def test_str_min_max_axis_1(how, dtype):
    # GH#56903 no cython groupby op for object-backed str min/max; the
    # axis=1 EA fastpath must fall back to python aggregation
    df = pd.DataFrame({"a": ["x", "b"], "b": ["c", "d"]}, dtype=dtype)
    result = getattr(df, how)(axis=1)
    values = ["c", "b"] if how == "min" else ["x", "d"]
    expected = pd.Series(values, dtype=dtype)
    tm.assert_series_equal(result, expected)


def test_third_party_ea_axis_1():
    # GH#56903 EAs without a _groupby_op override must fall back to
    # python aggregation in the axis=1 EA fastpath
    df = pd.DataFrame(
        {
            "a": DecimalArray([Decimal("1"), Decimal("2")]),
            "b": DecimalArray([Decimal("3"), Decimal("4")]),
        }
    )
    result = df.sum(axis=1)
    expected = pd.Series(DecimalArray([Decimal("4"), Decimal("6")]))
    tm.assert_series_equal(result, expected)


def test_mean_nullable_int_axis_1():
    # GH##36585
    df = pd.DataFrame(
        {"a": [1, 2, 3, 4], "b": pd.Series([1, 2, 4, None], dtype=pd.Int64Dtype())}
    )

    result = df.mean(axis=1, skipna=True)
    expected = pd.Series([1.0, 2.0, 3.5, 4.0], dtype="Float64")
    tm.assert_series_equal(result, expected)

    result = df.mean(axis=1, skipna=False)
    expected = pd.Series([1.0, 2.0, 3.5, pd.NA], dtype="Float64")
    tm.assert_series_equal(result, expected)


def test_numeric_only_validates_bool():
    # GH#53098
    df = pd.DataFrame({"A": [1, 2, 3], "B": [1.0, 2.0, 3.0], "C": ["x", "y", "z"]})
    df_num = pd.DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
    msg = "Passing non-boolean values for 'numeric_only' is deprecated"

    # _stat_function family: mean, min, max, median, skew, kurt
    for method in ["mean", "min", "max", "median", "skew", "kurt"]:
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only=1)
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only="yes")
        # None is falsy so _reduce includes all columns; use numeric-only df
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df_num, method)(numeric_only=None)

    # _stat_function_ddof family: std, var, sem
    for method in ["std", "var", "sem"]:
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only=1)
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only="yes")
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df_num, method)(numeric_only=None)

    # _min_count_stat_function family: sum, prod
    for method in ["sum", "prod"]:
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only=1)
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df, method)(numeric_only="yes")
        with tm.assert_produces_warning(Pandas4Warning, match=msg):
            getattr(df_num, method)(numeric_only=None)

    # Valid boolean values must still work (regression guard)
    df_num.mean(numeric_only=True)
    df_num.mean(numeric_only=False)
    df_num.sum(numeric_only=True)
    df_num.std(numeric_only=True)


@pytest.mark.parametrize("na_first", [True, False])
def test_median_skipna_false_keeps_complex(na_first):
    # GH#68487 the NaN propagated for a column holding an NA was real, so
    #  whenever that column was reduced first the others were cast down to it
    #  and lost their imaginary part
    cols = {"a": [1 + 2j, np.nan], "b": [1 + 2j, 3 + 4j]}
    if not na_first:
        cols = dict(reversed(cols.items()))
    df = pd.DataFrame(cols)

    expected = pd.Series(
        [complex(np.nan), 2 + 3j] if na_first else [2 + 3j, complex(np.nan)],
        index=list(cols),
    )
    tm.assert_series_equal(df.median(skipna=False), expected)
    tm.assert_series_equal(df.T.median(axis=1, skipna=False), expected)


@pytest.mark.parametrize(
    "method, expected",
    [
        ("sum", float(2**63) + 0.5),
        ("prod", float(2**62) * float(2**62) * 0.5),
        ("mean", (float(2**63) + 0.5) / 3),
    ],
)
def test_reduce_axis1_int_block_does_not_wrap(method, expected):
    # GH#68641: the int block used to be accumulated in int64, silently
    # wrapping, while the transpose path accumulates in float64
    df = pd.DataFrame({"a": [2**62], "b": [2**62], "c": [0.5]})
    assert len(df._mgr.blocks) > 1

    result = getattr(df, method)(axis=1)
    tm.assert_series_equal(result, pd.Series([expected]))
    tm.assert_series_equal(result, getattr(df.T, method)(), check_names=False)


def test_reduce_axis1_int_only_mean_widens_to_float64():
    # GH#68641: with no float column the common dtype is int64, so mean has to
    # widen it the way nanmean does or the sum wraps and flips sign
    df = pd.DataFrame({"a": [2**62], "b": [2**62], "c": np.array([1], dtype="uint8")})
    assert len(df._mgr.blocks) > 1

    result = df.mean(axis=1)
    tm.assert_series_equal(result, pd.Series([(float(2**63) + 1) / 3]))
    tm.assert_series_equal(result, df.T.mean(), check_names=False)


@pytest.mark.parametrize("method", ["sum", "prod", "mean"])
def test_reduce_axis1_uint64_block_does_not_wrap(method):
    # GH#68641
    df = pd.DataFrame(
        {
            "a": np.array([2**63], dtype="uint64"),
            "b": np.array([2**63], dtype="uint64"),
            "c": [0.5],
        }
    )
    assert len(df._mgr.blocks) > 1

    result = getattr(df, method)(axis=1)
    tm.assert_series_equal(result, getattr(df.T, method)(), check_names=False)
    # without the fix the uint64 block wrapped to 0, leaving just the float
    assert result.iloc[0] > 2**62


def test_reduce_axis1_int_uint_combine_stays_exact():
    # GH#68641: combining an int64 block result with a uint64 one promoted
    # the result to a lossy float64
    df = pd.DataFrame(
        {"a": np.array([2**62 + 1], dtype="int64"), "b": np.array([1], dtype="uint8")}
    )
    assert len(df._mgr.blocks) > 1

    result = df.sum(axis=1)
    tm.assert_series_equal(result, pd.Series([2**62 + 2], dtype="int64"))


@pytest.mark.parametrize("method", ["sum", "prod", "mean"])
def test_reduce_axis1_float32_not_upcast(method):
    # GH#68641: reducing in the common dtype keeps float32 out of float64
    df = pd.DataFrame(
        {
            "a": np.array([1.5, 2.5], dtype="float32"),
            "b": np.array([1, 2], dtype="int8"),
        }
    )
    assert len(df._mgr.blocks) > 1

    result = getattr(df, method)(axis=1)
    assert result.dtype == "float32"
    tm.assert_series_equal(result, getattr(df.T, method)(), check_names=False)


@pytest.mark.parametrize(
    "method, expected",
    [
        ("sum", float(2**63)),
        ("prod", float(2**62) * float(2**62) * 0.5),
        ("mean", float(2**63) / 4),
    ],
)
def test_reduce_axis1_bool_block_keeps_common_dtype(method, expected):
    # GH#68641: find_common_type would collapse to object here, which is why
    # the accumulation dtype comes from np.result_type instead
    df = pd.DataFrame({"a": [2**62], "b": [2**62], "c": [0.5], "d": [True]})
    assert len(df._mgr.blocks) == 3

    result = getattr(df, method)(axis=1)
    tm.assert_series_equal(result, pd.Series([expected]))


def test_reduce_axis1_complex64_matches_transpose():
    # GH#68641 nanmean accumulates in the input dtype and widens only for the
    # division, so complex64 must not be summed as complex128 here either
    df = pd.DataFrame(
        {
            "a": np.array([32767], dtype="int16"),
            "b": np.array([2**62], dtype="complex64"),
        }
    )
    assert len(df._mgr.blocks) > 1

    tm.assert_series_equal(df.mean(axis=1), df.T.mean())


@pytest.mark.parametrize("skipna", [True, False])
def test_reduce_axis1_min_count_complex64_matches_transpose(skipna):
    # GH#68641 _maybe_null_out widens complex64 before writing NaN; the axis=1
    # path has to widen the same way, and only where nanops does -- under
    # skipna=False it builds no mask, so nothing counts as missing
    df = pd.DataFrame(
        {
            "a": np.array([1 + 2j, np.nan], dtype="complex64"),
            "b": np.array([1.0, 2.0], dtype="float32"),
        }
    )
    assert len(df._mgr.blocks) > 1

    result = df.sum(axis=1, min_count=2, skipna=skipna)
    assert result.dtype == ("complex128" if skipna else "complex64")
    tm.assert_series_equal(result, df.T.sum(min_count=2, skipna=skipna))


def test_reduce_axis1_mean_complex_keeps_imaginary_part():
    # GH#68641: mean unconditionally cast the combined result to float64,
    # silently discarding the imaginary part
    df = pd.DataFrame(
        {"a": [True, False], "b": np.array([1 + 2j, 3 + 4j], dtype="complex64")}
    )
    assert len(df._mgr.blocks) > 1

    result = df.mean(axis=1)
    tm.assert_series_equal(result, pd.Series([1 + 1j, 1.5 + 2j], dtype="complex128"))


def test_reduce_axis1_bool_block_keeps_numpy_int_semantics():
    # GH#51474: a bool column no longer routes the reduction through object
    # dtype, so an integer result wraps like numpy instead of staying exact
    df = pd.DataFrame({"a": [2**62], "b": [2**62], "c": [True]})
    assert len(df._mgr.blocks) > 1

    result = df.sum(axis=1)
    expected = pd.Series([-(2**63) + 1])
    assert expected.dtype == "int64"
    tm.assert_series_equal(result, expected)


def test_reduce_axis1_float32_block_does_not_overflow():
    # GH#68641: the float32 block was accumulated in float32, overflowing to
    # inf where the transpose path accumulated in the common float64
    df = pd.DataFrame(
        {
            "a": np.array([3e38], dtype="float32"),
            "b": np.array([3e38], dtype="float32"),
            "c": [1.0],
        }
    )
    assert len(df._mgr.blocks) > 1

    result = df.sum(axis=1)
    tm.assert_series_equal(result, pd.Series([float(np.float32(3e38)) * 2 + 1.0]))
    tm.assert_series_equal(result, df.T.sum(), check_names=False)
