projektAI/venv/Lib/site-packages/pandas/tests/arrays/categorical/test_missing.py
2021-06-06 22:13:05 +02:00

182 lines
6.4 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])
with pytest.raises(ValueError, 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)
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]) # didnt 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]) # didnt 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 = pd.isna(cat)
tm.assert_numpy_array_equal(result, expected)
result = pd.isna(Series(cat))
expected = Series(expected)
tm.assert_series_equal(result, expected)
result = pd.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)