Inzynierka/Lib/site-packages/pandas/tests/indexes/multi/test_conversion.py
2023-06-02 12:51:02 +02:00

165 lines
4.8 KiB
Python

import numpy as np
import pytest
import pandas as pd
from pandas import (
DataFrame,
MultiIndex,
)
import pandas._testing as tm
def test_to_numpy(idx):
result = idx.to_numpy()
exp = idx.values
tm.assert_numpy_array_equal(result, exp)
def test_to_frame():
tuples = [(1, "one"), (1, "two"), (2, "one"), (2, "two")]
index = MultiIndex.from_tuples(tuples)
result = index.to_frame(index=False)
expected = DataFrame(tuples)
tm.assert_frame_equal(result, expected)
result = index.to_frame()
expected.index = index
tm.assert_frame_equal(result, expected)
tuples = [(1, "one"), (1, "two"), (2, "one"), (2, "two")]
index = MultiIndex.from_tuples(tuples, names=["first", "second"])
result = index.to_frame(index=False)
expected = DataFrame(tuples)
expected.columns = ["first", "second"]
tm.assert_frame_equal(result, expected)
result = index.to_frame()
expected.index = index
tm.assert_frame_equal(result, expected)
# See GH-22580
index = MultiIndex.from_tuples(tuples)
result = index.to_frame(index=False, name=["first", "second"])
expected = DataFrame(tuples)
expected.columns = ["first", "second"]
tm.assert_frame_equal(result, expected)
result = index.to_frame(name=["first", "second"])
expected.index = index
expected.columns = ["first", "second"]
tm.assert_frame_equal(result, expected)
msg = "'name' must be a list / sequence of column names."
with pytest.raises(TypeError, match=msg):
index.to_frame(name="first")
msg = "'name' should have same length as number of levels on index."
with pytest.raises(ValueError, match=msg):
index.to_frame(name=["first"])
# Tests for datetime index
index = MultiIndex.from_product([range(5), pd.date_range("20130101", periods=3)])
result = index.to_frame(index=False)
expected = DataFrame(
{
0: np.repeat(np.arange(5, dtype="int64"), 3),
1: np.tile(pd.date_range("20130101", periods=3), 5),
}
)
tm.assert_frame_equal(result, expected)
result = index.to_frame()
expected.index = index
tm.assert_frame_equal(result, expected)
# See GH-22580
result = index.to_frame(index=False, name=["first", "second"])
expected = DataFrame(
{
"first": np.repeat(np.arange(5, dtype="int64"), 3),
"second": np.tile(pd.date_range("20130101", periods=3), 5),
}
)
tm.assert_frame_equal(result, expected)
result = index.to_frame(name=["first", "second"])
expected.index = index
tm.assert_frame_equal(result, expected)
def test_to_frame_dtype_fidelity():
# GH 22420
mi = MultiIndex.from_arrays(
[
pd.date_range("19910905", periods=6, tz="US/Eastern"),
[1, 1, 1, 2, 2, 2],
pd.Categorical(["a", "a", "b", "b", "c", "c"], ordered=True),
["x", "x", "y", "z", "x", "y"],
],
names=["dates", "a", "b", "c"],
)
original_dtypes = {name: mi.levels[i].dtype for i, name in enumerate(mi.names)}
expected_df = DataFrame(
{
"dates": pd.date_range("19910905", periods=6, tz="US/Eastern"),
"a": [1, 1, 1, 2, 2, 2],
"b": pd.Categorical(["a", "a", "b", "b", "c", "c"], ordered=True),
"c": ["x", "x", "y", "z", "x", "y"],
}
)
df = mi.to_frame(index=False)
df_dtypes = df.dtypes.to_dict()
tm.assert_frame_equal(df, expected_df)
assert original_dtypes == df_dtypes
def test_to_frame_resulting_column_order():
# GH 22420
expected = ["z", 0, "a"]
mi = MultiIndex.from_arrays(
[["a", "b", "c"], ["x", "y", "z"], ["q", "w", "e"]], names=expected
)
result = mi.to_frame().columns.tolist()
assert result == expected
def test_to_frame_duplicate_labels():
# GH 45245
data = [(1, 2), (3, 4)]
names = ["a", "a"]
index = MultiIndex.from_tuples(data, names=names)
with pytest.raises(ValueError, match="Cannot create duplicate column labels"):
index.to_frame()
result = index.to_frame(allow_duplicates=True)
expected = DataFrame(data, index=index, columns=names)
tm.assert_frame_equal(result, expected)
names = [None, 0]
index = MultiIndex.from_tuples(data, names=names)
with pytest.raises(ValueError, match="Cannot create duplicate column labels"):
index.to_frame()
result = index.to_frame(allow_duplicates=True)
expected = DataFrame(data, index=index, columns=[0, 0])
tm.assert_frame_equal(result, expected)
def test_to_flat_index(idx):
expected = pd.Index(
(
("foo", "one"),
("foo", "two"),
("bar", "one"),
("baz", "two"),
("qux", "one"),
("qux", "two"),
),
tupleize_cols=False,
)
result = idx.to_flat_index()
tm.assert_index_equal(result, expected)