projektAI/venv/Lib/site-packages/pandas/tests/frame/indexing/test_xs.py
2021-06-06 22:13:05 +02:00

330 lines
12 KiB
Python

import re
import numpy as np
import pytest
from pandas import DataFrame, Index, IndexSlice, MultiIndex, Series, concat
import pandas._testing as tm
import pandas.core.common as com
from pandas.tseries.offsets import BDay
@pytest.fixture
def four_level_index_dataframe():
arr = np.array(
[
[-0.5109, -2.3358, -0.4645, 0.05076, 0.364],
[0.4473, 1.4152, 0.2834, 1.00661, 0.1744],
[-0.6662, -0.5243, -0.358, 0.89145, 2.5838],
]
)
index = MultiIndex(
levels=[["a", "x"], ["b", "q"], [10.0032, 20.0, 30.0], [3, 4, 5]],
codes=[[0, 0, 1], [0, 1, 1], [0, 1, 2], [2, 1, 0]],
names=["one", "two", "three", "four"],
)
return DataFrame(arr, index=index, columns=list("ABCDE"))
class TestXS:
def test_xs(self, float_frame, datetime_frame):
idx = float_frame.index[5]
xs = float_frame.xs(idx)
for item, value in xs.items():
if np.isnan(value):
assert np.isnan(float_frame[item][idx])
else:
assert value == float_frame[item][idx]
# mixed-type xs
test_data = {"A": {"1": 1, "2": 2}, "B": {"1": "1", "2": "2", "3": "3"}}
frame = DataFrame(test_data)
xs = frame.xs("1")
assert xs.dtype == np.object_
assert xs["A"] == 1
assert xs["B"] == "1"
with pytest.raises(
KeyError, match=re.escape("Timestamp('1999-12-31 00:00:00', freq='B')")
):
datetime_frame.xs(datetime_frame.index[0] - BDay())
# xs get column
series = float_frame.xs("A", axis=1)
expected = float_frame["A"]
tm.assert_series_equal(series, expected)
# view is returned if possible
series = float_frame.xs("A", axis=1)
series[:] = 5
assert (expected == 5).all()
def test_xs_corner(self):
# pathological mixed-type reordering case
df = DataFrame(index=[0])
df["A"] = 1.0
df["B"] = "foo"
df["C"] = 2.0
df["D"] = "bar"
df["E"] = 3.0
xs = df.xs(0)
exp = Series([1.0, "foo", 2.0, "bar", 3.0], index=list("ABCDE"), name=0)
tm.assert_series_equal(xs, exp)
# no columns but Index(dtype=object)
df = DataFrame(index=["a", "b", "c"])
result = df.xs("a")
expected = Series([], name="a", index=Index([]), dtype=np.float64)
tm.assert_series_equal(result, expected)
def test_xs_duplicates(self):
df = DataFrame(np.random.randn(5, 2), index=["b", "b", "c", "b", "a"])
cross = df.xs("c")
exp = df.iloc[2]
tm.assert_series_equal(cross, exp)
def test_xs_keep_level(self):
df = DataFrame(
{
"day": {0: "sat", 1: "sun"},
"flavour": {0: "strawberry", 1: "strawberry"},
"sales": {0: 10, 1: 12},
"year": {0: 2008, 1: 2008},
}
).set_index(["year", "flavour", "day"])
result = df.xs("sat", level="day", drop_level=False)
expected = df[:1]
tm.assert_frame_equal(result, expected)
result = df.xs([2008, "sat"], level=["year", "day"], drop_level=False)
tm.assert_frame_equal(result, expected)
def test_xs_view(self):
# in 0.14 this will return a view if possible a copy otherwise, but
# this is numpy dependent
dm = DataFrame(np.arange(20.0).reshape(4, 5), index=range(4), columns=range(5))
dm.xs(2)[:] = 10
assert (dm.xs(2) == 10).all()
class TestXSWithMultiIndex:
def test_xs_integer_key(self):
# see GH#2107
dates = range(20111201, 20111205)
ids = list("abcde")
index = MultiIndex.from_product([dates, ids], names=["date", "secid"])
df = DataFrame(np.random.randn(len(index), 3), index, ["X", "Y", "Z"])
result = df.xs(20111201, level="date")
expected = df.loc[20111201, :]
tm.assert_frame_equal(result, expected)
def test_xs_level(self, multiindex_dataframe_random_data):
df = multiindex_dataframe_random_data
result = df.xs("two", level="second")
expected = df[df.index.get_level_values(1) == "two"]
expected.index = Index(["foo", "bar", "baz", "qux"], name="first")
tm.assert_frame_equal(result, expected)
def test_xs_level_eq_2(self):
arr = np.random.randn(3, 5)
index = MultiIndex(
levels=[["a", "p", "x"], ["b", "q", "y"], ["c", "r", "z"]],
codes=[[2, 0, 1], [2, 0, 1], [2, 0, 1]],
)
df = DataFrame(arr, index=index)
expected = DataFrame(arr[1:2], index=[["a"], ["b"]])
result = df.xs("c", level=2)
tm.assert_frame_equal(result, expected)
def test_xs_setting_with_copy_error(self, multiindex_dataframe_random_data):
# this is a copy in 0.14
df = multiindex_dataframe_random_data
result = df.xs("two", level="second")
# setting this will give a SettingWithCopyError
# as we are trying to write a view
msg = "A value is trying to be set on a copy of a slice from a DataFrame"
with pytest.raises(com.SettingWithCopyError, match=msg):
result[:] = 10
def test_xs_setting_with_copy_error_multiple(self, four_level_index_dataframe):
# this is a copy in 0.14
df = four_level_index_dataframe
result = df.xs(("a", 4), level=["one", "four"])
# setting this will give a SettingWithCopyError
# as we are trying to write a view
msg = "A value is trying to be set on a copy of a slice from a DataFrame"
with pytest.raises(com.SettingWithCopyError, match=msg):
result[:] = 10
@pytest.mark.parametrize("key, level", [("one", "second"), (["one"], ["second"])])
def test_xs_with_duplicates(self, key, level, multiindex_dataframe_random_data):
# see GH#13719
frame = multiindex_dataframe_random_data
df = concat([frame] * 2)
assert df.index.is_unique is False
expected = concat([frame.xs("one", level="second")] * 2)
result = df.xs(key, level=level)
tm.assert_frame_equal(result, expected)
def test_xs_missing_values_in_index(self):
# see GH#6574
# missing values in returned index should be preserved
acc = [
("a", "abcde", 1),
("b", "bbcde", 2),
("y", "yzcde", 25),
("z", "xbcde", 24),
("z", None, 26),
("z", "zbcde", 25),
("z", "ybcde", 26),
]
df = DataFrame(acc, columns=["a1", "a2", "cnt"]).set_index(["a1", "a2"])
expected = DataFrame(
{"cnt": [24, 26, 25, 26]},
index=Index(["xbcde", np.nan, "zbcde", "ybcde"], name="a2"),
)
result = df.xs("z", level="a1")
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"key, level, exp_arr, exp_index",
[
("a", "lvl0", lambda x: x[:, 0:2], Index(["bar", "foo"], name="lvl1")),
("foo", "lvl1", lambda x: x[:, 1:2], Index(["a"], name="lvl0")),
],
)
def test_xs_named_levels_axis_eq_1(self, key, level, exp_arr, exp_index):
# see GH#2903
arr = np.random.randn(4, 4)
index = MultiIndex(
levels=[["a", "b"], ["bar", "foo", "hello", "world"]],
codes=[[0, 0, 1, 1], [0, 1, 2, 3]],
names=["lvl0", "lvl1"],
)
df = DataFrame(arr, columns=index)
result = df.xs(key, level=level, axis=1)
expected = DataFrame(exp_arr(arr), columns=exp_index)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"indexer",
[
lambda df: df.xs(("a", 4), level=["one", "four"]),
lambda df: df.xs("a").xs(4, level="four"),
],
)
def test_xs_level_multiple(self, indexer, four_level_index_dataframe):
df = four_level_index_dataframe
expected_values = [[0.4473, 1.4152, 0.2834, 1.00661, 0.1744]]
expected_index = MultiIndex(
levels=[["q"], [20.0]], codes=[[0], [0]], names=["two", "three"]
)
expected = DataFrame(
expected_values, index=expected_index, columns=list("ABCDE")
)
result = indexer(df)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"indexer", [lambda df: df.xs("a", level=0), lambda df: df.xs("a")]
)
def test_xs_level0(self, indexer, four_level_index_dataframe):
df = four_level_index_dataframe
expected_values = [
[-0.5109, -2.3358, -0.4645, 0.05076, 0.364],
[0.4473, 1.4152, 0.2834, 1.00661, 0.1744],
]
expected_index = MultiIndex(
levels=[["b", "q"], [10.0032, 20.0], [4, 5]],
codes=[[0, 1], [0, 1], [1, 0]],
names=["two", "three", "four"],
)
expected = DataFrame(
expected_values, index=expected_index, columns=list("ABCDE")
)
result = indexer(df)
tm.assert_frame_equal(result, expected)
def test_xs_values(self, multiindex_dataframe_random_data):
df = multiindex_dataframe_random_data
result = df.xs(("bar", "two")).values
expected = df.values[4]
tm.assert_almost_equal(result, expected)
def test_xs_loc_equality(self, multiindex_dataframe_random_data):
df = multiindex_dataframe_random_data
result = df.xs(("bar", "two"))
expected = df.loc[("bar", "two")]
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize("klass", [DataFrame, Series])
def test_xs_IndexSlice_argument_not_implemented(self, klass):
# GH#35301
index = MultiIndex(
levels=[[("foo", "bar", 0), ("foo", "baz", 0), ("foo", "qux", 0)], [0, 1]],
codes=[[0, 0, 1, 1, 2, 2], [0, 1, 0, 1, 0, 1]],
)
obj = DataFrame(np.random.randn(6, 4), index=index)
if klass is Series:
obj = obj[0]
msg = (
"Expected label or tuple of labels, got "
r"\(\('foo', 'qux', 0\), slice\(None, None, None\)\)"
)
with pytest.raises(TypeError, match=msg):
obj.xs(IndexSlice[("foo", "qux", 0), :])
@pytest.mark.parametrize("klass", [DataFrame, Series])
def test_xs_levels_raises(self, klass):
obj = DataFrame({"A": [1, 2, 3]})
if klass is Series:
obj = obj["A"]
msg = "Index must be a MultiIndex"
with pytest.raises(TypeError, match=msg):
obj.xs(0, level="as")
def test_xs_multiindex_droplevel_false(self):
# GH#19056
mi = MultiIndex.from_tuples(
[("a", "x"), ("a", "y"), ("b", "x")], names=["level1", "level2"]
)
df = DataFrame([[1, 2, 3]], columns=mi)
result = df.xs("a", axis=1, drop_level=False)
expected = DataFrame(
[[1, 2]],
columns=MultiIndex.from_tuples(
[("a", "x"), ("a", "y")], names=["level1", "level2"]
),
)
tm.assert_frame_equal(result, expected)
def test_xs_droplevel_false(self):
# GH#19056
df = DataFrame([[1, 2, 3]], columns=Index(["a", "b", "c"]))
result = df.xs("a", axis=1, drop_level=False)
expected = DataFrame({"a": [1]})
tm.assert_frame_equal(result, expected)
def test_xs_droplevel_false_view(self):
# GH#37832
df = DataFrame([[1, 2, 3]], columns=Index(["a", "b", "c"]))
result = df.xs("a", axis=1, drop_level=False)
df.values[0, 0] = 2
expected = DataFrame({"a": [2]})
tm.assert_frame_equal(result, expected)