3RNN/Lib/site-packages/pandas/tests/indexes/multi/test_names.py
2024-05-26 19:49:15 +02:00

202 lines
6.4 KiB
Python

import pytest
import pandas as pd
from pandas import MultiIndex
import pandas._testing as tm
def check_level_names(index, names):
assert [level.name for level in index.levels] == list(names)
def test_slice_keep_name():
x = MultiIndex.from_tuples([("a", "b"), (1, 2), ("c", "d")], names=["x", "y"])
assert x[1:].names == x.names
def test_index_name_retained():
# GH9857
result = pd.DataFrame({"x": [1, 2, 6], "y": [2, 2, 8], "z": [-5, 0, 5]})
result = result.set_index("z")
result.loc[10] = [9, 10]
df_expected = pd.DataFrame(
{"x": [1, 2, 6, 9], "y": [2, 2, 8, 10], "z": [-5, 0, 5, 10]}
)
df_expected = df_expected.set_index("z")
tm.assert_frame_equal(result, df_expected)
def test_changing_names(idx):
assert [level.name for level in idx.levels] == ["first", "second"]
view = idx.view()
copy = idx.copy()
shallow_copy = idx._view()
# changing names should not change level names on object
new_names = [name + "a" for name in idx.names]
idx.names = new_names
check_level_names(idx, ["firsta", "seconda"])
# and not on copies
check_level_names(view, ["first", "second"])
check_level_names(copy, ["first", "second"])
check_level_names(shallow_copy, ["first", "second"])
# and copies shouldn't change original
shallow_copy.names = [name + "c" for name in shallow_copy.names]
check_level_names(idx, ["firsta", "seconda"])
def test_take_preserve_name(idx):
taken = idx.take([3, 0, 1])
assert taken.names == idx.names
def test_copy_names():
# Check that adding a "names" parameter to the copy is honored
# GH14302
multi_idx = MultiIndex.from_tuples([(1, 2), (3, 4)], names=["MyName1", "MyName2"])
multi_idx1 = multi_idx.copy()
assert multi_idx.equals(multi_idx1)
assert multi_idx.names == ["MyName1", "MyName2"]
assert multi_idx1.names == ["MyName1", "MyName2"]
multi_idx2 = multi_idx.copy(names=["NewName1", "NewName2"])
assert multi_idx.equals(multi_idx2)
assert multi_idx.names == ["MyName1", "MyName2"]
assert multi_idx2.names == ["NewName1", "NewName2"]
multi_idx3 = multi_idx.copy(name=["NewName1", "NewName2"])
assert multi_idx.equals(multi_idx3)
assert multi_idx.names == ["MyName1", "MyName2"]
assert multi_idx3.names == ["NewName1", "NewName2"]
# gh-35592
with pytest.raises(ValueError, match="Length of new names must be 2, got 1"):
multi_idx.copy(names=["mario"])
with pytest.raises(TypeError, match="MultiIndex.name must be a hashable type"):
multi_idx.copy(names=[["mario"], ["luigi"]])
def test_names(idx):
# names are assigned in setup
assert idx.names == ["first", "second"]
level_names = [level.name for level in idx.levels]
assert level_names == idx.names
# setting bad names on existing
index = idx
with pytest.raises(ValueError, match="^Length of names"):
setattr(index, "names", list(index.names) + ["third"])
with pytest.raises(ValueError, match="^Length of names"):
setattr(index, "names", [])
# initializing with bad names (should always be equivalent)
major_axis, minor_axis = idx.levels
major_codes, minor_codes = idx.codes
with pytest.raises(ValueError, match="^Length of names"):
MultiIndex(
levels=[major_axis, minor_axis],
codes=[major_codes, minor_codes],
names=["first"],
)
with pytest.raises(ValueError, match="^Length of names"):
MultiIndex(
levels=[major_axis, minor_axis],
codes=[major_codes, minor_codes],
names=["first", "second", "third"],
)
# names are assigned on index, but not transferred to the levels
index.names = ["a", "b"]
level_names = [level.name for level in index.levels]
assert level_names == ["a", "b"]
def test_duplicate_level_names_access_raises(idx):
# GH19029
idx.names = ["foo", "foo"]
with pytest.raises(ValueError, match="name foo occurs multiple times"):
idx._get_level_number("foo")
def test_get_names_from_levels():
idx = MultiIndex.from_product([["a"], [1, 2]], names=["a", "b"])
assert idx.levels[0].name == "a"
assert idx.levels[1].name == "b"
def test_setting_names_from_levels_raises():
idx = MultiIndex.from_product([["a"], [1, 2]], names=["a", "b"])
with pytest.raises(RuntimeError, match="set_names"):
idx.levels[0].name = "foo"
with pytest.raises(RuntimeError, match="set_names"):
idx.levels[1].name = "foo"
new = pd.Series(1, index=idx.levels[0])
with pytest.raises(RuntimeError, match="set_names"):
new.index.name = "bar"
assert pd.Index._no_setting_name is False
assert pd.RangeIndex._no_setting_name is False
@pytest.mark.parametrize("func", ["rename", "set_names"])
@pytest.mark.parametrize(
"rename_dict, exp_names",
[
({"x": "z"}, ["z", "y", "z"]),
({"x": "z", "y": "x"}, ["z", "x", "z"]),
({"y": "z"}, ["x", "z", "x"]),
({}, ["x", "y", "x"]),
({"z": "a"}, ["x", "y", "x"]),
({"y": "z", "a": "b"}, ["x", "z", "x"]),
],
)
def test_name_mi_with_dict_like_duplicate_names(func, rename_dict, exp_names):
# GH#20421
mi = MultiIndex.from_arrays([[1, 2], [3, 4], [5, 6]], names=["x", "y", "x"])
result = getattr(mi, func)(rename_dict)
expected = MultiIndex.from_arrays([[1, 2], [3, 4], [5, 6]], names=exp_names)
tm.assert_index_equal(result, expected)
@pytest.mark.parametrize("func", ["rename", "set_names"])
@pytest.mark.parametrize(
"rename_dict, exp_names",
[
({"x": "z"}, ["z", "y"]),
({"x": "z", "y": "x"}, ["z", "x"]),
({"a": "z"}, ["x", "y"]),
({}, ["x", "y"]),
],
)
def test_name_mi_with_dict_like(func, rename_dict, exp_names):
# GH#20421
mi = MultiIndex.from_arrays([[1, 2], [3, 4]], names=["x", "y"])
result = getattr(mi, func)(rename_dict)
expected = MultiIndex.from_arrays([[1, 2], [3, 4]], names=exp_names)
tm.assert_index_equal(result, expected)
def test_index_name_with_dict_like_raising():
# GH#20421
ix = pd.Index([1, 2])
msg = "Can only pass dict-like as `names` for MultiIndex."
with pytest.raises(TypeError, match=msg):
ix.set_names({"x": "z"})
def test_multiindex_name_and_level_raising():
# GH#20421
mi = MultiIndex.from_arrays([[1, 2], [3, 4]], names=["x", "y"])
with pytest.raises(TypeError, match="Can not pass level for dictlike `names`."):
mi.set_names(names={"x": "z"}, level={"x": "z"})