Inzynierka/Lib/site-packages/pandas/tests/arrays/categorical/test_missing.py
2023-06-02 12:51:02 +02:00

213 lines
7.3 KiB
Python

import collections
import numpy as np
import pytest
from pandas.core.dtypes.dtypes import CategoricalDtype
import pandas as pd
from pandas import (
Categorical,
DataFrame,
Index,
Series,
isna,
)
import pandas._testing as tm
class TestCategoricalMissing:
def test_isna(self):
exp = np.array([False, False, True])
cat = Categorical(["a", "b", np.nan])
res = cat.isna()
tm.assert_numpy_array_equal(res, exp)
def test_na_flags_int_categories(self):
# #1457
categories = list(range(10))
labels = np.random.randint(0, 10, 20)
labels[::5] = -1
cat = Categorical(labels, categories, fastpath=True)
repr(cat)
tm.assert_numpy_array_equal(isna(cat), labels == -1)
def test_nan_handling(self):
# Nans are represented as -1 in codes
c = Categorical(["a", "b", np.nan, "a"])
tm.assert_index_equal(c.categories, Index(["a", "b"]))
tm.assert_numpy_array_equal(c._codes, np.array([0, 1, -1, 0], dtype=np.int8))
c[1] = np.nan
tm.assert_index_equal(c.categories, Index(["a", "b"]))
tm.assert_numpy_array_equal(c._codes, np.array([0, -1, -1, 0], dtype=np.int8))
# Adding nan to categories should make assigned nan point to the
# category!
c = Categorical(["a", "b", np.nan, "a"])
tm.assert_index_equal(c.categories, Index(["a", "b"]))
tm.assert_numpy_array_equal(c._codes, np.array([0, 1, -1, 0], dtype=np.int8))
def test_set_dtype_nans(self):
c = Categorical(["a", "b", np.nan])
result = c._set_dtype(CategoricalDtype(["a", "c"]))
tm.assert_numpy_array_equal(result.codes, np.array([0, -1, -1], dtype="int8"))
def test_set_item_nan(self):
cat = Categorical([1, 2, 3])
cat[1] = np.nan
exp = Categorical([1, np.nan, 3], categories=[1, 2, 3])
tm.assert_categorical_equal(cat, exp)
@pytest.mark.parametrize(
"fillna_kwargs, msg",
[
(
{"value": 1, "method": "ffill"},
"Cannot specify both 'value' and 'method'.",
),
({}, "Must specify a fill 'value' or 'method'."),
({"method": "bad"}, "Invalid fill method. Expecting .* bad"),
(
{"value": Series([1, 2, 3, 4, "a"])},
"Cannot setitem on a Categorical with a new category",
),
],
)
def test_fillna_raises(self, fillna_kwargs, msg):
# https://github.com/pandas-dev/pandas/issues/19682
# https://github.com/pandas-dev/pandas/issues/13628
cat = Categorical([1, 2, 3, None, None])
if len(fillna_kwargs) == 1 and "value" in fillna_kwargs:
err = TypeError
else:
err = ValueError
with pytest.raises(err, match=msg):
cat.fillna(**fillna_kwargs)
@pytest.mark.parametrize("named", [True, False])
def test_fillna_iterable_category(self, named):
# https://github.com/pandas-dev/pandas/issues/21097
if named:
Point = collections.namedtuple("Point", "x y")
else:
Point = lambda *args: args # tuple
cat = Categorical(np.array([Point(0, 0), Point(0, 1), None], dtype=object))
result = cat.fillna(Point(0, 0))
expected = Categorical([Point(0, 0), Point(0, 1), Point(0, 0)])
tm.assert_categorical_equal(result, expected)
# Case where the Point is not among our categories; we want ValueError,
# not NotImplementedError GH#41914
cat = Categorical(np.array([Point(1, 0), Point(0, 1), None], dtype=object))
msg = "Cannot setitem on a Categorical with a new category"
with pytest.raises(TypeError, match=msg):
cat.fillna(Point(0, 0))
def test_fillna_array(self):
# accept Categorical or ndarray value if it holds appropriate values
cat = Categorical(["A", "B", "C", None, None])
other = cat.fillna("C")
result = cat.fillna(other)
tm.assert_categorical_equal(result, other)
assert isna(cat[-1]) # didn't modify original inplace
other = np.array(["A", "B", "C", "B", "A"])
result = cat.fillna(other)
expected = Categorical(["A", "B", "C", "B", "A"], dtype=cat.dtype)
tm.assert_categorical_equal(result, expected)
assert isna(cat[-1]) # didn't modify original inplace
@pytest.mark.parametrize(
"values, expected",
[
([1, 2, 3], np.array([False, False, False])),
([1, 2, np.nan], np.array([False, False, True])),
([1, 2, np.inf], np.array([False, False, True])),
([1, 2, pd.NA], np.array([False, False, True])),
],
)
def test_use_inf_as_na(self, values, expected):
# https://github.com/pandas-dev/pandas/issues/33594
with pd.option_context("mode.use_inf_as_na", True):
cat = Categorical(values)
result = cat.isna()
tm.assert_numpy_array_equal(result, expected)
result = Series(cat).isna()
expected = Series(expected)
tm.assert_series_equal(result, expected)
result = DataFrame(cat).isna()
expected = DataFrame(expected)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"values, expected",
[
([1, 2, 3], np.array([False, False, False])),
([1, 2, np.nan], np.array([False, False, True])),
([1, 2, np.inf], np.array([False, False, True])),
([1, 2, pd.NA], np.array([False, False, True])),
],
)
def test_use_inf_as_na_outside_context(self, values, expected):
# https://github.com/pandas-dev/pandas/issues/33594
# Using isna directly for Categorical will fail in general here
cat = Categorical(values)
with pd.option_context("mode.use_inf_as_na", True):
result = isna(cat)
tm.assert_numpy_array_equal(result, expected)
result = isna(Series(cat))
expected = Series(expected)
tm.assert_series_equal(result, expected)
result = isna(DataFrame(cat))
expected = DataFrame(expected)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"a1, a2, categories",
[
(["a", "b", "c"], [np.nan, "a", "b"], ["a", "b", "c"]),
([1, 2, 3], [np.nan, 1, 2], [1, 2, 3]),
],
)
def test_compare_categorical_with_missing(self, a1, a2, categories):
# GH 28384
cat_type = CategoricalDtype(categories)
# !=
result = Series(a1, dtype=cat_type) != Series(a2, dtype=cat_type)
expected = Series(a1) != Series(a2)
tm.assert_series_equal(result, expected)
# ==
result = Series(a1, dtype=cat_type) == Series(a2, dtype=cat_type)
expected = Series(a1) == Series(a2)
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize(
"na_value, dtype",
[
(pd.NaT, "datetime64[ns]"),
(None, "float64"),
(np.nan, "float64"),
(pd.NA, "float64"),
],
)
def test_categorical_only_missing_values_no_cast(self, na_value, dtype):
# GH#44900
result = Categorical([na_value, na_value])
tm.assert_index_equal(result.categories, Index([], dtype=dtype))