laywerrobot/lib/python3.6/site-packages/pandas/tests/categorical/test_algos.py
2020-08-27 21:55:39 +02:00

113 lines
4 KiB
Python

import pytest
import numpy as np
import pandas as pd
import pandas.util.testing as tm
@pytest.mark.parametrize('ordered', [True, False])
@pytest.mark.parametrize('categories', [
['b', 'a', 'c'],
['a', 'b', 'c', 'd'],
])
def test_factorize(categories, ordered):
cat = pd.Categorical(['b', 'b', 'a', 'c', None],
categories=categories,
ordered=ordered)
labels, uniques = pd.factorize(cat)
expected_labels = np.array([0, 0, 1, 2, -1], dtype=np.intp)
expected_uniques = pd.Categorical(['b', 'a', 'c'],
categories=categories,
ordered=ordered)
tm.assert_numpy_array_equal(labels, expected_labels)
tm.assert_categorical_equal(uniques, expected_uniques)
def test_factorized_sort():
cat = pd.Categorical(['b', 'b', None, 'a'])
labels, uniques = pd.factorize(cat, sort=True)
expected_labels = np.array([1, 1, -1, 0], dtype=np.intp)
expected_uniques = pd.Categorical(['a', 'b'])
tm.assert_numpy_array_equal(labels, expected_labels)
tm.assert_categorical_equal(uniques, expected_uniques)
def test_factorized_sort_ordered():
cat = pd.Categorical(['b', 'b', None, 'a'],
categories=['c', 'b', 'a'],
ordered=True)
labels, uniques = pd.factorize(cat, sort=True)
expected_labels = np.array([0, 0, -1, 1], dtype=np.intp)
expected_uniques = pd.Categorical(['b', 'a'],
categories=['c', 'b', 'a'],
ordered=True)
tm.assert_numpy_array_equal(labels, expected_labels)
tm.assert_categorical_equal(uniques, expected_uniques)
def test_isin_cats():
# GH2003
cat = pd.Categorical(["a", "b", np.nan])
result = cat.isin(["a", np.nan])
expected = np.array([True, False, True], dtype=bool)
tm.assert_numpy_array_equal(expected, result)
result = cat.isin(["a", "c"])
expected = np.array([True, False, False], dtype=bool)
tm.assert_numpy_array_equal(expected, result)
@pytest.mark.parametrize("empty", [[], pd.Series(), np.array([])])
def test_isin_empty(empty):
s = pd.Categorical(["a", "b"])
expected = np.array([False, False], dtype=bool)
result = s.isin(empty)
tm.assert_numpy_array_equal(expected, result)
class TestTake(object):
# https://github.com/pandas-dev/pandas/issues/20664
def test_take_warns(self):
cat = pd.Categorical(['a', 'b'])
with tm.assert_produces_warning(FutureWarning):
cat.take([0, -1])
def test_take_positive_no_warning(self):
cat = pd.Categorical(['a', 'b'])
with tm.assert_produces_warning(None):
cat.take([0, 0])
def test_take_bounds(self, allow_fill):
# https://github.com/pandas-dev/pandas/issues/20664
cat = pd.Categorical(['a', 'b', 'a'])
with pytest.raises(IndexError):
cat.take([4, 5], allow_fill=allow_fill)
def test_take_empty(self, allow_fill):
# https://github.com/pandas-dev/pandas/issues/20664
cat = pd.Categorical([], categories=['a', 'b'])
with pytest.raises(IndexError):
cat.take([0], allow_fill=allow_fill)
def test_positional_take(self, ordered):
cat = pd.Categorical(['a', 'a', 'b', 'b'], categories=['b', 'a'],
ordered=ordered)
result = cat.take([0, 1, 2], allow_fill=False)
expected = pd.Categorical(['a', 'a', 'b'], categories=cat.categories,
ordered=ordered)
tm.assert_categorical_equal(result, expected)
def test_positional_take_unobserved(self, ordered):
cat = pd.Categorical(['a', 'b'], categories=['a', 'b', 'c'],
ordered=ordered)
result = cat.take([1, 0], allow_fill=False)
expected = pd.Categorical(['b', 'a'], categories=cat.categories,
ordered=ordered)
tm.assert_categorical_equal(result, expected)