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

494 lines
19 KiB
Python

import re
import numpy as np
import pytest
from pandas.compat import PY311
from pandas import (
Categorical,
CategoricalIndex,
DataFrame,
Index,
Series,
StringDtype,
)
import pandas._testing as tm
from pandas.core.arrays.categorical import recode_for_categories
class TestCategoricalAPI:
def test_ordered_api(self):
# GH 9347
cat1 = Categorical(list("acb"), ordered=False)
tm.assert_index_equal(cat1.categories, Index(["a", "b", "c"]))
assert not cat1.ordered
cat2 = Categorical(list("acb"), categories=list("bca"), ordered=False)
tm.assert_index_equal(cat2.categories, Index(["b", "c", "a"]))
assert not cat2.ordered
cat3 = Categorical(list("acb"), ordered=True)
tm.assert_index_equal(cat3.categories, Index(["a", "b", "c"]))
assert cat3.ordered
cat4 = Categorical(list("acb"), categories=list("bca"), ordered=True)
tm.assert_index_equal(cat4.categories, Index(["b", "c", "a"]))
assert cat4.ordered
def test_set_ordered(self):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
cat2 = cat.as_unordered()
assert not cat2.ordered
cat2 = cat.as_ordered()
assert cat2.ordered
assert cat2.set_ordered(True).ordered
assert not cat2.set_ordered(False).ordered
# removed in 0.19.0
msg = (
"property 'ordered' of 'Categorical' object has no setter"
if PY311
else "can't set attribute"
)
with pytest.raises(AttributeError, match=msg):
cat.ordered = True
with pytest.raises(AttributeError, match=msg):
cat.ordered = False
def test_rename_categories(self):
cat = Categorical(["a", "b", "c", "a"])
# inplace=False: the old one must not be changed
res = cat.rename_categories([1, 2, 3])
tm.assert_numpy_array_equal(
res.__array__(), np.array([1, 2, 3, 1], dtype=np.int64)
)
tm.assert_index_equal(res.categories, Index([1, 2, 3]))
exp_cat = np.array(["a", "b", "c", "a"], dtype=np.object_)
tm.assert_numpy_array_equal(cat.__array__(), exp_cat)
exp_cat = Index(["a", "b", "c"])
tm.assert_index_equal(cat.categories, exp_cat)
# GH18862 (let rename_categories take callables)
result = cat.rename_categories(lambda x: x.upper())
expected = Categorical(["A", "B", "C", "A"])
tm.assert_categorical_equal(result, expected)
@pytest.mark.parametrize("new_categories", [[1, 2, 3, 4], [1, 2]])
def test_rename_categories_wrong_length_raises(self, new_categories):
cat = Categorical(["a", "b", "c", "a"])
msg = (
"new categories need to have the same number of items as the "
"old categories!"
)
with pytest.raises(ValueError, match=msg):
cat.rename_categories(new_categories)
def test_rename_categories_series(self):
# https://github.com/pandas-dev/pandas/issues/17981
c = Categorical(["a", "b"])
result = c.rename_categories(Series([0, 1], index=["a", "b"]))
expected = Categorical([0, 1])
tm.assert_categorical_equal(result, expected)
def test_rename_categories_dict(self):
# GH 17336
cat = Categorical(["a", "b", "c", "d"])
res = cat.rename_categories({"a": 4, "b": 3, "c": 2, "d": 1})
expected = Index([4, 3, 2, 1])
tm.assert_index_equal(res.categories, expected)
# Test for dicts of smaller length
cat = Categorical(["a", "b", "c", "d"])
res = cat.rename_categories({"a": 1, "c": 3})
expected = Index([1, "b", 3, "d"])
tm.assert_index_equal(res.categories, expected)
# Test for dicts with bigger length
cat = Categorical(["a", "b", "c", "d"])
res = cat.rename_categories({"a": 1, "b": 2, "c": 3, "d": 4, "e": 5, "f": 6})
expected = Index([1, 2, 3, 4])
tm.assert_index_equal(res.categories, expected)
# Test for dicts with no items from old categories
cat = Categorical(["a", "b", "c", "d"])
res = cat.rename_categories({"f": 1, "g": 3})
expected = Index(["a", "b", "c", "d"])
tm.assert_index_equal(res.categories, expected)
def test_reorder_categories(self):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
old = cat.copy()
new = Categorical(
["a", "b", "c", "a"], categories=["c", "b", "a"], ordered=True
)
res = cat.reorder_categories(["c", "b", "a"])
# cat must be the same as before
tm.assert_categorical_equal(cat, old)
# only res is changed
tm.assert_categorical_equal(res, new)
@pytest.mark.parametrize(
"new_categories",
[
["a"], # not all "old" included in "new"
["a", "b", "d"], # still not all "old" in "new"
["a", "b", "c", "d"], # all "old" included in "new", but too long
],
)
def test_reorder_categories_raises(self, new_categories):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
msg = "items in new_categories are not the same as in old categories"
with pytest.raises(ValueError, match=msg):
cat.reorder_categories(new_categories)
def test_add_categories(self):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
old = cat.copy()
new = Categorical(
["a", "b", "c", "a"], categories=["a", "b", "c", "d"], ordered=True
)
res = cat.add_categories("d")
tm.assert_categorical_equal(cat, old)
tm.assert_categorical_equal(res, new)
res = cat.add_categories(["d"])
tm.assert_categorical_equal(cat, old)
tm.assert_categorical_equal(res, new)
# GH 9927
cat = Categorical(list("abc"), ordered=True)
expected = Categorical(list("abc"), categories=list("abcde"), ordered=True)
# test with Series, np.array, index, list
res = cat.add_categories(Series(["d", "e"]))
tm.assert_categorical_equal(res, expected)
res = cat.add_categories(np.array(["d", "e"]))
tm.assert_categorical_equal(res, expected)
res = cat.add_categories(Index(["d", "e"]))
tm.assert_categorical_equal(res, expected)
res = cat.add_categories(["d", "e"])
tm.assert_categorical_equal(res, expected)
def test_add_categories_existing_raises(self):
# new is in old categories
cat = Categorical(["a", "b", "c", "d"], ordered=True)
msg = re.escape("new categories must not include old categories: {'d'}")
with pytest.raises(ValueError, match=msg):
cat.add_categories(["d"])
def test_add_categories_losing_dtype_information(self):
# GH#48812
cat = Categorical(Series([1, 2], dtype="Int64"))
ser = Series([4], dtype="Int64")
result = cat.add_categories(ser)
expected = Categorical(
Series([1, 2], dtype="Int64"), categories=Series([1, 2, 4], dtype="Int64")
)
tm.assert_categorical_equal(result, expected)
cat = Categorical(Series(["a", "b", "a"], dtype=StringDtype()))
ser = Series(["d"], dtype=StringDtype())
result = cat.add_categories(ser)
expected = Categorical(
Series(["a", "b", "a"], dtype=StringDtype()),
categories=Series(["a", "b", "d"], dtype=StringDtype()),
)
tm.assert_categorical_equal(result, expected)
def test_set_categories(self):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
exp_categories = Index(["c", "b", "a"])
exp_values = np.array(["a", "b", "c", "a"], dtype=np.object_)
cat = cat.set_categories(["c", "b", "a"])
res = cat.set_categories(["a", "b", "c"])
# cat must be the same as before
tm.assert_index_equal(cat.categories, exp_categories)
tm.assert_numpy_array_equal(cat.__array__(), exp_values)
# only res is changed
exp_categories_back = Index(["a", "b", "c"])
tm.assert_index_equal(res.categories, exp_categories_back)
tm.assert_numpy_array_equal(res.__array__(), exp_values)
# not all "old" included in "new" -> all not included ones are now
# np.nan
cat = Categorical(["a", "b", "c", "a"], ordered=True)
res = cat.set_categories(["a"])
tm.assert_numpy_array_equal(res.codes, np.array([0, -1, -1, 0], dtype=np.int8))
# still not all "old" in "new"
res = cat.set_categories(["a", "b", "d"])
tm.assert_numpy_array_equal(res.codes, np.array([0, 1, -1, 0], dtype=np.int8))
tm.assert_index_equal(res.categories, Index(["a", "b", "d"]))
# all "old" included in "new"
cat = cat.set_categories(["a", "b", "c", "d"])
exp_categories = Index(["a", "b", "c", "d"])
tm.assert_index_equal(cat.categories, exp_categories)
# internals...
c = Categorical([1, 2, 3, 4, 1], categories=[1, 2, 3, 4], ordered=True)
tm.assert_numpy_array_equal(c._codes, np.array([0, 1, 2, 3, 0], dtype=np.int8))
tm.assert_index_equal(c.categories, Index([1, 2, 3, 4]))
exp = np.array([1, 2, 3, 4, 1], dtype=np.int64)
tm.assert_numpy_array_equal(np.asarray(c), exp)
# all "pointers" to '4' must be changed from 3 to 0,...
c = c.set_categories([4, 3, 2, 1])
# positions are changed
tm.assert_numpy_array_equal(c._codes, np.array([3, 2, 1, 0, 3], dtype=np.int8))
# categories are now in new order
tm.assert_index_equal(c.categories, Index([4, 3, 2, 1]))
# output is the same
exp = np.array([1, 2, 3, 4, 1], dtype=np.int64)
tm.assert_numpy_array_equal(np.asarray(c), exp)
assert c.min() == 4
assert c.max() == 1
# set_categories should set the ordering if specified
c2 = c.set_categories([4, 3, 2, 1], ordered=False)
assert not c2.ordered
tm.assert_numpy_array_equal(np.asarray(c), np.asarray(c2))
# set_categories should pass thru the ordering
c2 = c.set_ordered(False).set_categories([4, 3, 2, 1])
assert not c2.ordered
tm.assert_numpy_array_equal(np.asarray(c), np.asarray(c2))
@pytest.mark.parametrize(
"values, categories, new_categories",
[
# No NaNs, same cats, same order
(["a", "b", "a"], ["a", "b"], ["a", "b"]),
# No NaNs, same cats, different order
(["a", "b", "a"], ["a", "b"], ["b", "a"]),
# Same, unsorted
(["b", "a", "a"], ["a", "b"], ["a", "b"]),
# No NaNs, same cats, different order
(["b", "a", "a"], ["a", "b"], ["b", "a"]),
# NaNs
(["a", "b", "c"], ["a", "b"], ["a", "b"]),
(["a", "b", "c"], ["a", "b"], ["b", "a"]),
(["b", "a", "c"], ["a", "b"], ["a", "b"]),
(["b", "a", "c"], ["a", "b"], ["a", "b"]),
# Introduce NaNs
(["a", "b", "c"], ["a", "b"], ["a"]),
(["a", "b", "c"], ["a", "b"], ["b"]),
(["b", "a", "c"], ["a", "b"], ["a"]),
(["b", "a", "c"], ["a", "b"], ["a"]),
# No overlap
(["a", "b", "c"], ["a", "b"], ["d", "e"]),
],
)
@pytest.mark.parametrize("ordered", [True, False])
def test_set_categories_many(self, values, categories, new_categories, ordered):
c = Categorical(values, categories)
expected = Categorical(values, new_categories, ordered)
result = c.set_categories(new_categories, ordered=ordered)
tm.assert_categorical_equal(result, expected)
def test_set_categories_rename_less(self):
# GH 24675
cat = Categorical(["A", "B"])
result = cat.set_categories(["A"], rename=True)
expected = Categorical(["A", np.nan])
tm.assert_categorical_equal(result, expected)
def test_set_categories_private(self):
cat = Categorical(["a", "b", "c"], categories=["a", "b", "c", "d"])
cat._set_categories(["a", "c", "d", "e"])
expected = Categorical(["a", "c", "d"], categories=list("acde"))
tm.assert_categorical_equal(cat, expected)
# fastpath
cat = Categorical(["a", "b", "c"], categories=["a", "b", "c", "d"])
cat._set_categories(["a", "c", "d", "e"], fastpath=True)
expected = Categorical(["a", "c", "d"], categories=list("acde"))
tm.assert_categorical_equal(cat, expected)
def test_remove_categories(self):
cat = Categorical(["a", "b", "c", "a"], ordered=True)
old = cat.copy()
new = Categorical(["a", "b", np.nan, "a"], categories=["a", "b"], ordered=True)
res = cat.remove_categories("c")
tm.assert_categorical_equal(cat, old)
tm.assert_categorical_equal(res, new)
res = cat.remove_categories(["c"])
tm.assert_categorical_equal(cat, old)
tm.assert_categorical_equal(res, new)
@pytest.mark.parametrize("removals", [["c"], ["c", np.nan], "c", ["c", "c"]])
def test_remove_categories_raises(self, removals):
cat = Categorical(["a", "b", "a"])
message = re.escape("removals must all be in old categories: {'c'}")
with pytest.raises(ValueError, match=message):
cat.remove_categories(removals)
def test_remove_unused_categories(self):
c = Categorical(["a", "b", "c", "d", "a"], categories=["a", "b", "c", "d", "e"])
exp_categories_all = Index(["a", "b", "c", "d", "e"])
exp_categories_dropped = Index(["a", "b", "c", "d"])
tm.assert_index_equal(c.categories, exp_categories_all)
res = c.remove_unused_categories()
tm.assert_index_equal(res.categories, exp_categories_dropped)
tm.assert_index_equal(c.categories, exp_categories_all)
# with NaN values (GH11599)
c = Categorical(["a", "b", "c", np.nan], categories=["a", "b", "c", "d", "e"])
res = c.remove_unused_categories()
tm.assert_index_equal(res.categories, Index(np.array(["a", "b", "c"])))
exp_codes = np.array([0, 1, 2, -1], dtype=np.int8)
tm.assert_numpy_array_equal(res.codes, exp_codes)
tm.assert_index_equal(c.categories, exp_categories_all)
val = ["F", np.nan, "D", "B", "D", "F", np.nan]
cat = Categorical(values=val, categories=list("ABCDEFG"))
out = cat.remove_unused_categories()
tm.assert_index_equal(out.categories, Index(["B", "D", "F"]))
exp_codes = np.array([2, -1, 1, 0, 1, 2, -1], dtype=np.int8)
tm.assert_numpy_array_equal(out.codes, exp_codes)
assert out.tolist() == val
alpha = list("abcdefghijklmnopqrstuvwxyz")
val = np.random.choice(alpha[::2], 10000).astype("object")
val[np.random.choice(len(val), 100)] = np.nan
cat = Categorical(values=val, categories=alpha)
out = cat.remove_unused_categories()
assert out.tolist() == val.tolist()
class TestCategoricalAPIWithFactor:
def test_describe(self, factor):
# string type
desc = factor.describe()
assert factor.ordered
exp_index = CategoricalIndex(
["a", "b", "c"], name="categories", ordered=factor.ordered
)
expected = DataFrame(
{"counts": [3, 2, 3], "freqs": [3 / 8.0, 2 / 8.0, 3 / 8.0]}, index=exp_index
)
tm.assert_frame_equal(desc, expected)
# check unused categories
cat = factor.copy()
cat = cat.set_categories(["a", "b", "c", "d"])
desc = cat.describe()
exp_index = CategoricalIndex(
list("abcd"), ordered=factor.ordered, name="categories"
)
expected = DataFrame(
{"counts": [3, 2, 3, 0], "freqs": [3 / 8.0, 2 / 8.0, 3 / 8.0, 0]},
index=exp_index,
)
tm.assert_frame_equal(desc, expected)
# check an integer one
cat = Categorical([1, 2, 3, 1, 2, 3, 3, 2, 1, 1, 1])
desc = cat.describe()
exp_index = CategoricalIndex([1, 2, 3], ordered=cat.ordered, name="categories")
expected = DataFrame(
{"counts": [5, 3, 3], "freqs": [5 / 11.0, 3 / 11.0, 3 / 11.0]},
index=exp_index,
)
tm.assert_frame_equal(desc, expected)
# https://github.com/pandas-dev/pandas/issues/3678
# describe should work with NaN
cat = Categorical([np.nan, 1, 2, 2])
desc = cat.describe()
expected = DataFrame(
{"counts": [1, 2, 1], "freqs": [1 / 4.0, 2 / 4.0, 1 / 4.0]},
index=CategoricalIndex(
[1, 2, np.nan], categories=[1, 2], name="categories"
),
)
tm.assert_frame_equal(desc, expected)
class TestPrivateCategoricalAPI:
def test_codes_immutable(self):
# Codes should be read only
c = Categorical(["a", "b", "c", "a", np.nan])
exp = np.array([0, 1, 2, 0, -1], dtype="int8")
tm.assert_numpy_array_equal(c.codes, exp)
# Assignments to codes should raise
msg = (
"property 'codes' of 'Categorical' object has no setter"
if PY311
else "can't set attribute"
)
with pytest.raises(AttributeError, match=msg):
c.codes = np.array([0, 1, 2, 0, 1], dtype="int8")
# changes in the codes array should raise
codes = c.codes
with pytest.raises(ValueError, match="assignment destination is read-only"):
codes[4] = 1
# But even after getting the codes, the original array should still be
# writeable!
c[4] = "a"
exp = np.array([0, 1, 2, 0, 0], dtype="int8")
tm.assert_numpy_array_equal(c.codes, exp)
c._codes[4] = 2
exp = np.array([0, 1, 2, 0, 2], dtype="int8")
tm.assert_numpy_array_equal(c.codes, exp)
@pytest.mark.parametrize(
"codes, old, new, expected",
[
([0, 1], ["a", "b"], ["a", "b"], [0, 1]),
([0, 1], ["b", "a"], ["b", "a"], [0, 1]),
([0, 1], ["a", "b"], ["b", "a"], [1, 0]),
([0, 1], ["b", "a"], ["a", "b"], [1, 0]),
([0, 1, 0, 1], ["a", "b"], ["a", "b", "c"], [0, 1, 0, 1]),
([0, 1, 2, 2], ["a", "b", "c"], ["a", "b"], [0, 1, -1, -1]),
([0, 1, -1], ["a", "b", "c"], ["a", "b", "c"], [0, 1, -1]),
([0, 1, -1], ["a", "b", "c"], ["b"], [-1, 0, -1]),
([0, 1, -1], ["a", "b", "c"], ["d"], [-1, -1, -1]),
([0, 1, -1], ["a", "b", "c"], [], [-1, -1, -1]),
([-1, -1], [], ["a", "b"], [-1, -1]),
([1, 0], ["b", "a"], ["a", "b"], [0, 1]),
],
)
def test_recode_to_categories(self, codes, old, new, expected):
codes = np.asanyarray(codes, dtype=np.int8)
expected = np.asanyarray(expected, dtype=np.int8)
old = Index(old)
new = Index(new)
result = recode_for_categories(codes, old, new)
tm.assert_numpy_array_equal(result, expected)
def test_recode_to_categories_large(self):
N = 1000
codes = np.arange(N)
old = Index(codes)
expected = np.arange(N - 1, -1, -1, dtype=np.int16)
new = Index(expected)
result = recode_for_categories(codes, old, new)
tm.assert_numpy_array_equal(result, expected)