zmc
2023-12-22 9fdbf60165db0400c2e8e6be2dc6e88138ac719a
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
import pytest
 
from pandas import (
    DataFrame,
    Index,
    MultiIndex,
)
import pandas._testing as tm
 
 
class TestDropLevel:
    def test_droplevel(self, frame_or_series):
        # GH#20342
        cols = MultiIndex.from_tuples(
            [("c", "e"), ("d", "f")], names=["level_1", "level_2"]
        )
        mi = MultiIndex.from_tuples([(1, 2), (5, 6), (9, 10)], names=["a", "b"])
        df = DataFrame([[3, 4], [7, 8], [11, 12]], index=mi, columns=cols)
        if frame_or_series is not DataFrame:
            df = df.iloc[:, 0]
 
        # test that dropping of a level in index works
        expected = df.reset_index("a", drop=True)
        result = df.droplevel("a", axis="index")
        tm.assert_equal(result, expected)
 
        if frame_or_series is DataFrame:
            # test that dropping of a level in columns works
            expected = df.copy()
            expected.columns = Index(["c", "d"], name="level_1")
            result = df.droplevel("level_2", axis="columns")
            tm.assert_equal(result, expected)
        else:
            # test that droplevel raises ValueError on axis != 0
            with pytest.raises(ValueError, match="No axis named columns"):
                df.droplevel(1, axis="columns")