Traktor/myenv/Lib/site-packages/sklearn/utils/tests/test_encode.py
2024-05-23 01:57:24 +02:00

275 lines
9.4 KiB
Python

import pickle
import numpy as np
import pytest
from numpy.testing import assert_array_equal
from sklearn.utils._encode import _check_unknown, _encode, _get_counts, _unique
@pytest.mark.parametrize(
"values, expected",
[
(np.array([2, 1, 3, 1, 3], dtype="int64"), np.array([1, 2, 3], dtype="int64")),
(
np.array([2, 1, np.nan, 1, np.nan], dtype="float32"),
np.array([1, 2, np.nan], dtype="float32"),
),
(
np.array(["b", "a", "c", "a", "c"], dtype=object),
np.array(["a", "b", "c"], dtype=object),
),
(
np.array(["b", "a", None, "a", None], dtype=object),
np.array(["a", "b", None], dtype=object),
),
(np.array(["b", "a", "c", "a", "c"]), np.array(["a", "b", "c"])),
],
ids=["int64", "float32-nan", "object", "object-None", "str"],
)
def test_encode_util(values, expected):
uniques = _unique(values)
assert_array_equal(uniques, expected)
result, encoded = _unique(values, return_inverse=True)
assert_array_equal(result, expected)
assert_array_equal(encoded, np.array([1, 0, 2, 0, 2]))
encoded = _encode(values, uniques=uniques)
assert_array_equal(encoded, np.array([1, 0, 2, 0, 2]))
result, counts = _unique(values, return_counts=True)
assert_array_equal(result, expected)
assert_array_equal(counts, np.array([2, 1, 2]))
result, encoded, counts = _unique(values, return_inverse=True, return_counts=True)
assert_array_equal(result, expected)
assert_array_equal(encoded, np.array([1, 0, 2, 0, 2]))
assert_array_equal(counts, np.array([2, 1, 2]))
def test_encode_with_check_unknown():
# test for the check_unknown parameter of _encode()
uniques = np.array([1, 2, 3])
values = np.array([1, 2, 3, 4])
# Default is True, raise error
with pytest.raises(ValueError, match="y contains previously unseen labels"):
_encode(values, uniques=uniques, check_unknown=True)
# dont raise error if False
_encode(values, uniques=uniques, check_unknown=False)
# parameter is ignored for object dtype
uniques = np.array(["a", "b", "c"], dtype=object)
values = np.array(["a", "b", "c", "d"], dtype=object)
with pytest.raises(ValueError, match="y contains previously unseen labels"):
_encode(values, uniques=uniques, check_unknown=False)
def _assert_check_unknown(values, uniques, expected_diff, expected_mask):
diff = _check_unknown(values, uniques)
assert_array_equal(diff, expected_diff)
diff, valid_mask = _check_unknown(values, uniques, return_mask=True)
assert_array_equal(diff, expected_diff)
assert_array_equal(valid_mask, expected_mask)
@pytest.mark.parametrize(
"values, uniques, expected_diff, expected_mask",
[
(np.array([1, 2, 3, 4]), np.array([1, 2, 3]), [4], [True, True, True, False]),
(np.array([2, 1, 4, 5]), np.array([2, 5, 1]), [4], [True, True, False, True]),
(np.array([2, 1, np.nan]), np.array([2, 5, 1]), [np.nan], [True, True, False]),
(
np.array([2, 1, 4, np.nan]),
np.array([2, 5, 1, np.nan]),
[4],
[True, True, False, True],
),
(
np.array([2, 1, 4, np.nan]),
np.array([2, 5, 1]),
[4, np.nan],
[True, True, False, False],
),
(
np.array([2, 1, 4, 5]),
np.array([2, 5, 1, np.nan]),
[4],
[True, True, False, True],
),
(
np.array(["a", "b", "c", "d"], dtype=object),
np.array(["a", "b", "c"], dtype=object),
np.array(["d"], dtype=object),
[True, True, True, False],
),
(
np.array(["d", "c", "a", "b"], dtype=object),
np.array(["a", "c", "b"], dtype=object),
np.array(["d"], dtype=object),
[False, True, True, True],
),
(
np.array(["a", "b", "c", "d"]),
np.array(["a", "b", "c"]),
np.array(["d"]),
[True, True, True, False],
),
(
np.array(["d", "c", "a", "b"]),
np.array(["a", "c", "b"]),
np.array(["d"]),
[False, True, True, True],
),
],
)
def test_check_unknown(values, uniques, expected_diff, expected_mask):
_assert_check_unknown(values, uniques, expected_diff, expected_mask)
@pytest.mark.parametrize("missing_value", [None, np.nan, float("nan")])
@pytest.mark.parametrize("pickle_uniques", [True, False])
def test_check_unknown_missing_values(missing_value, pickle_uniques):
# check for check_unknown with missing values with object dtypes
values = np.array(["d", "c", "a", "b", missing_value], dtype=object)
uniques = np.array(["c", "a", "b", missing_value], dtype=object)
if pickle_uniques:
uniques = pickle.loads(pickle.dumps(uniques))
expected_diff = ["d"]
expected_mask = [False, True, True, True, True]
_assert_check_unknown(values, uniques, expected_diff, expected_mask)
values = np.array(["d", "c", "a", "b", missing_value], dtype=object)
uniques = np.array(["c", "a", "b"], dtype=object)
if pickle_uniques:
uniques = pickle.loads(pickle.dumps(uniques))
expected_diff = ["d", missing_value]
expected_mask = [False, True, True, True, False]
_assert_check_unknown(values, uniques, expected_diff, expected_mask)
values = np.array(["a", missing_value], dtype=object)
uniques = np.array(["a", "b", "z"], dtype=object)
if pickle_uniques:
uniques = pickle.loads(pickle.dumps(uniques))
expected_diff = [missing_value]
expected_mask = [True, False]
_assert_check_unknown(values, uniques, expected_diff, expected_mask)
@pytest.mark.parametrize("missing_value", [np.nan, None, float("nan")])
@pytest.mark.parametrize("pickle_uniques", [True, False])
def test_unique_util_missing_values_objects(missing_value, pickle_uniques):
# check for _unique and _encode with missing values with object dtypes
values = np.array(["a", "c", "c", missing_value, "b"], dtype=object)
expected_uniques = np.array(["a", "b", "c", missing_value], dtype=object)
uniques = _unique(values)
if missing_value is None:
assert_array_equal(uniques, expected_uniques)
else: # missing_value == np.nan
assert_array_equal(uniques[:-1], expected_uniques[:-1])
assert np.isnan(uniques[-1])
if pickle_uniques:
uniques = pickle.loads(pickle.dumps(uniques))
encoded = _encode(values, uniques=uniques)
assert_array_equal(encoded, np.array([0, 2, 2, 3, 1]))
def test_unique_util_missing_values_numeric():
# Check missing values in numerical values
values = np.array([3, 1, np.nan, 5, 3, np.nan], dtype=float)
expected_uniques = np.array([1, 3, 5, np.nan], dtype=float)
expected_inverse = np.array([1, 0, 3, 2, 1, 3])
uniques = _unique(values)
assert_array_equal(uniques, expected_uniques)
uniques, inverse = _unique(values, return_inverse=True)
assert_array_equal(uniques, expected_uniques)
assert_array_equal(inverse, expected_inverse)
encoded = _encode(values, uniques=uniques)
assert_array_equal(encoded, expected_inverse)
def test_unique_util_with_all_missing_values():
# test for all types of missing values for object dtype
values = np.array([np.nan, "a", "c", "c", None, float("nan"), None], dtype=object)
uniques = _unique(values)
assert_array_equal(uniques[:-1], ["a", "c", None])
# last value is nan
assert np.isnan(uniques[-1])
expected_inverse = [3, 0, 1, 1, 2, 3, 2]
_, inverse = _unique(values, return_inverse=True)
assert_array_equal(inverse, expected_inverse)
def test_check_unknown_with_both_missing_values():
# test for both types of missing values for object dtype
values = np.array([np.nan, "a", "c", "c", None, np.nan, None], dtype=object)
diff = _check_unknown(values, known_values=np.array(["a", "c"], dtype=object))
assert diff[0] is None
assert np.isnan(diff[1])
diff, valid_mask = _check_unknown(
values, known_values=np.array(["a", "c"], dtype=object), return_mask=True
)
assert diff[0] is None
assert np.isnan(diff[1])
assert_array_equal(valid_mask, [False, True, True, True, False, False, False])
@pytest.mark.parametrize(
"values, uniques, expected_counts",
[
(np.array([1] * 10 + [2] * 4 + [3] * 15), np.array([1, 2, 3]), [10, 4, 15]),
(
np.array([1] * 10 + [2] * 4 + [3] * 15),
np.array([1, 2, 3, 5]),
[10, 4, 15, 0],
),
(
np.array([np.nan] * 10 + [2] * 4 + [3] * 15),
np.array([2, 3, np.nan]),
[4, 15, 10],
),
(
np.array(["b"] * 4 + ["a"] * 16 + ["c"] * 20, dtype=object),
["a", "b", "c"],
[16, 4, 20],
),
(
np.array(["b"] * 4 + ["a"] * 16 + ["c"] * 20, dtype=object),
["c", "b", "a"],
[20, 4, 16],
),
(
np.array([np.nan] * 4 + ["a"] * 16 + ["c"] * 20, dtype=object),
["c", np.nan, "a"],
[20, 4, 16],
),
(
np.array(["b"] * 4 + ["a"] * 16 + ["c"] * 20, dtype=object),
["a", "b", "c", "e"],
[16, 4, 20, 0],
),
],
)
def test_get_counts(values, uniques, expected_counts):
counts = _get_counts(values, uniques)
assert_array_equal(counts, expected_counts)