ai-content-maker/.venv/Lib/site-packages/sklearn/utils/tests/test_utils.py

867 lines
29 KiB
Python

import string
import timeit
import warnings
from copy import copy
from itertools import chain
from unittest import SkipTest
import numpy as np
import pytest
from sklearn import config_context
from sklearn.externals._packaging.version import parse as parse_version
from sklearn.utils import (
_approximate_mode,
_determine_key_type,
_get_column_indices,
_is_polars_df,
_message_with_time,
_print_elapsed_time,
_safe_assign,
_safe_indexing,
_to_object_array,
check_random_state,
column_or_1d,
deprecated,
gen_even_slices,
get_chunk_n_rows,
is_scalar_nan,
resample,
safe_mask,
shuffle,
)
from sklearn.utils._mocking import MockDataFrame
from sklearn.utils._testing import (
_convert_container,
assert_allclose_dense_sparse,
assert_array_equal,
assert_no_warnings,
)
from sklearn.utils.fixes import CSC_CONTAINERS, CSR_CONTAINERS
# toy array
X_toy = np.arange(9).reshape((3, 3))
def test_make_rng():
# Check the check_random_state utility function behavior
assert check_random_state(None) is np.random.mtrand._rand
assert check_random_state(np.random) is np.random.mtrand._rand
rng_42 = np.random.RandomState(42)
assert check_random_state(42).randint(100) == rng_42.randint(100)
rng_42 = np.random.RandomState(42)
assert check_random_state(rng_42) is rng_42
rng_42 = np.random.RandomState(42)
assert check_random_state(43).randint(100) != rng_42.randint(100)
with pytest.raises(ValueError):
check_random_state("some invalid seed")
def test_deprecated():
# Test whether the deprecated decorator issues appropriate warnings
# Copied almost verbatim from https://docs.python.org/library/warnings.html
# First a function...
with warnings.catch_warnings(record=True) as w:
warnings.simplefilter("always")
@deprecated()
def ham():
return "spam"
spam = ham()
assert spam == "spam" # function must remain usable
assert len(w) == 1
assert issubclass(w[0].category, FutureWarning)
assert "deprecated" in str(w[0].message).lower()
# ... then a class.
with warnings.catch_warnings(record=True) as w:
warnings.simplefilter("always")
@deprecated("don't use this")
class Ham:
SPAM = 1
ham = Ham()
assert hasattr(ham, "SPAM")
assert len(w) == 1
assert issubclass(w[0].category, FutureWarning)
assert "deprecated" in str(w[0].message).lower()
def test_resample():
# Border case not worth mentioning in doctests
assert resample() is None
# Check that invalid arguments yield ValueError
with pytest.raises(ValueError):
resample([0], [0, 1])
with pytest.raises(ValueError):
resample([0, 1], [0, 1], replace=False, n_samples=3)
# Issue:6581, n_samples can be more when replace is True (default).
assert len(resample([1, 2], n_samples=5)) == 5
def test_resample_stratified():
# Make sure resample can stratify
rng = np.random.RandomState(0)
n_samples = 100
p = 0.9
X = rng.normal(size=(n_samples, 1))
y = rng.binomial(1, p, size=n_samples)
_, y_not_stratified = resample(X, y, n_samples=10, random_state=0, stratify=None)
assert np.all(y_not_stratified == 1)
_, y_stratified = resample(X, y, n_samples=10, random_state=0, stratify=y)
assert not np.all(y_stratified == 1)
assert np.sum(y_stratified) == 9 # all 1s, one 0
def test_resample_stratified_replace():
# Make sure stratified resampling supports the replace parameter
rng = np.random.RandomState(0)
n_samples = 100
X = rng.normal(size=(n_samples, 1))
y = rng.randint(0, 2, size=n_samples)
X_replace, _ = resample(
X, y, replace=True, n_samples=50, random_state=rng, stratify=y
)
X_no_replace, _ = resample(
X, y, replace=False, n_samples=50, random_state=rng, stratify=y
)
assert np.unique(X_replace).shape[0] < 50
assert np.unique(X_no_replace).shape[0] == 50
# make sure n_samples can be greater than X.shape[0] if we sample with
# replacement
X_replace, _ = resample(
X, y, replace=True, n_samples=1000, random_state=rng, stratify=y
)
assert X_replace.shape[0] == 1000
assert np.unique(X_replace).shape[0] == 100
def test_resample_stratify_2dy():
# Make sure y can be 2d when stratifying
rng = np.random.RandomState(0)
n_samples = 100
X = rng.normal(size=(n_samples, 1))
y = rng.randint(0, 2, size=(n_samples, 2))
X, y = resample(X, y, n_samples=50, random_state=rng, stratify=y)
assert y.ndim == 2
@pytest.mark.parametrize("csr_container", CSR_CONTAINERS)
def test_resample_stratify_sparse_error(csr_container):
# resample must be ndarray
rng = np.random.RandomState(0)
n_samples = 100
X = rng.normal(size=(n_samples, 2))
y = rng.randint(0, 2, size=n_samples)
stratify = csr_container(y.reshape(-1, 1))
with pytest.raises(TypeError, match="Sparse data was passed"):
X, y = resample(X, y, n_samples=50, random_state=rng, stratify=stratify)
@pytest.mark.parametrize("csr_container", CSR_CONTAINERS)
def test_safe_mask(csr_container):
random_state = check_random_state(0)
X = random_state.rand(5, 4)
X_csr = csr_container(X)
mask = [False, False, True, True, True]
mask = safe_mask(X, mask)
assert X[mask].shape[0] == 3
mask = safe_mask(X_csr, mask)
assert X_csr[mask].shape[0] == 3
def test_column_or_1d():
EXAMPLES = [
("binary", ["spam", "egg", "spam"]),
("binary", [0, 1, 0, 1]),
("continuous", np.arange(10) / 20.0),
("multiclass", [1, 2, 3]),
("multiclass", [0, 1, 2, 2, 0]),
("multiclass", [[1], [2], [3]]),
("multilabel-indicator", [[0, 1, 0], [0, 0, 1]]),
("multiclass-multioutput", [[1, 2, 3]]),
("multiclass-multioutput", [[1, 1], [2, 2], [3, 1]]),
("multiclass-multioutput", [[5, 1], [4, 2], [3, 1]]),
("multiclass-multioutput", [[1, 2, 3]]),
("continuous-multioutput", np.arange(30).reshape((-1, 3))),
]
for y_type, y in EXAMPLES:
if y_type in ["binary", "multiclass", "continuous"]:
assert_array_equal(column_or_1d(y), np.ravel(y))
else:
with pytest.raises(ValueError):
column_or_1d(y)
@pytest.mark.parametrize(
"key, dtype",
[
(0, "int"),
("0", "str"),
(True, "bool"),
(np.bool_(True), "bool"),
([0, 1, 2], "int"),
(["0", "1", "2"], "str"),
((0, 1, 2), "int"),
(("0", "1", "2"), "str"),
(slice(None, None), None),
(slice(0, 2), "int"),
(np.array([0, 1, 2], dtype=np.int32), "int"),
(np.array([0, 1, 2], dtype=np.int64), "int"),
(np.array([0, 1, 2], dtype=np.uint8), "int"),
([True, False], "bool"),
((True, False), "bool"),
(np.array([True, False]), "bool"),
("col_0", "str"),
(["col_0", "col_1", "col_2"], "str"),
(("col_0", "col_1", "col_2"), "str"),
(slice("begin", "end"), "str"),
(np.array(["col_0", "col_1", "col_2"]), "str"),
(np.array(["col_0", "col_1", "col_2"], dtype=object), "str"),
],
)
def test_determine_key_type(key, dtype):
assert _determine_key_type(key) == dtype
def test_determine_key_type_error():
with pytest.raises(ValueError, match="No valid specification of the"):
_determine_key_type(1.0)
def test_determine_key_type_slice_error():
with pytest.raises(TypeError, match="Only array-like or scalar are"):
_determine_key_type(slice(0, 2, 1), accept_slice=False)
@pytest.mark.parametrize("array_type", ["list", "array", "sparse", "dataframe"])
@pytest.mark.parametrize("indices_type", ["list", "tuple", "array", "series", "slice"])
def test_safe_indexing_2d_container_axis_0(array_type, indices_type):
indices = [1, 2]
if indices_type == "slice" and isinstance(indices[1], int):
indices[1] += 1
array = _convert_container([[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type)
indices = _convert_container(indices, indices_type)
subset = _safe_indexing(array, indices, axis=0)
assert_allclose_dense_sparse(
subset, _convert_container([[4, 5, 6], [7, 8, 9]], array_type)
)
@pytest.mark.parametrize("array_type", ["list", "array", "series"])
@pytest.mark.parametrize("indices_type", ["list", "tuple", "array", "series", "slice"])
def test_safe_indexing_1d_container(array_type, indices_type):
indices = [1, 2]
if indices_type == "slice" and isinstance(indices[1], int):
indices[1] += 1
array = _convert_container([1, 2, 3, 4, 5, 6, 7, 8, 9], array_type)
indices = _convert_container(indices, indices_type)
subset = _safe_indexing(array, indices, axis=0)
assert_allclose_dense_sparse(subset, _convert_container([2, 3], array_type))
@pytest.mark.parametrize("array_type", ["array", "sparse", "dataframe"])
@pytest.mark.parametrize("indices_type", ["list", "tuple", "array", "series", "slice"])
@pytest.mark.parametrize("indices", [[1, 2], ["col_1", "col_2"]])
def test_safe_indexing_2d_container_axis_1(array_type, indices_type, indices):
# validation of the indices
# we make a copy because indices is mutable and shared between tests
indices_converted = copy(indices)
if indices_type == "slice" and isinstance(indices[1], int):
indices_converted[1] += 1
columns_name = ["col_0", "col_1", "col_2"]
array = _convert_container(
[[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type, columns_name
)
indices_converted = _convert_container(indices_converted, indices_type)
if isinstance(indices[0], str) and array_type != "dataframe":
err_msg = (
"Specifying the columns using strings is only supported for dataframes"
)
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(array, indices_converted, axis=1)
else:
subset = _safe_indexing(array, indices_converted, axis=1)
assert_allclose_dense_sparse(
subset, _convert_container([[2, 3], [5, 6], [8, 9]], array_type)
)
@pytest.mark.parametrize("array_read_only", [True, False])
@pytest.mark.parametrize("indices_read_only", [True, False])
@pytest.mark.parametrize("array_type", ["array", "sparse", "dataframe"])
@pytest.mark.parametrize("indices_type", ["array", "series"])
@pytest.mark.parametrize(
"axis, expected_array", [(0, [[4, 5, 6], [7, 8, 9]]), (1, [[2, 3], [5, 6], [8, 9]])]
)
def test_safe_indexing_2d_read_only_axis_1(
array_read_only, indices_read_only, array_type, indices_type, axis, expected_array
):
array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
if array_read_only:
array.setflags(write=False)
array = _convert_container(array, array_type)
indices = np.array([1, 2])
if indices_read_only:
indices.setflags(write=False)
indices = _convert_container(indices, indices_type)
subset = _safe_indexing(array, indices, axis=axis)
assert_allclose_dense_sparse(subset, _convert_container(expected_array, array_type))
@pytest.mark.parametrize("array_type", ["list", "array", "series"])
@pytest.mark.parametrize("indices_type", ["list", "tuple", "array", "series"])
def test_safe_indexing_1d_container_mask(array_type, indices_type):
indices = [False] + [True] * 2 + [False] * 6
array = _convert_container([1, 2, 3, 4, 5, 6, 7, 8, 9], array_type)
indices = _convert_container(indices, indices_type)
subset = _safe_indexing(array, indices, axis=0)
assert_allclose_dense_sparse(subset, _convert_container([2, 3], array_type))
@pytest.mark.parametrize("array_type", ["array", "sparse", "dataframe"])
@pytest.mark.parametrize("indices_type", ["list", "tuple", "array", "series"])
@pytest.mark.parametrize(
"axis, expected_subset",
[(0, [[4, 5, 6], [7, 8, 9]]), (1, [[2, 3], [5, 6], [8, 9]])],
)
def test_safe_indexing_2d_mask(array_type, indices_type, axis, expected_subset):
columns_name = ["col_0", "col_1", "col_2"]
array = _convert_container(
[[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type, columns_name
)
indices = [False, True, True]
indices = _convert_container(indices, indices_type)
subset = _safe_indexing(array, indices, axis=axis)
assert_allclose_dense_sparse(
subset, _convert_container(expected_subset, array_type)
)
@pytest.mark.parametrize(
"array_type, expected_output_type",
[
("list", "list"),
("array", "array"),
("sparse", "sparse"),
("dataframe", "series"),
],
)
def test_safe_indexing_2d_scalar_axis_0(array_type, expected_output_type):
array = _convert_container([[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type)
indices = 2
subset = _safe_indexing(array, indices, axis=0)
expected_array = _convert_container([7, 8, 9], expected_output_type)
assert_allclose_dense_sparse(subset, expected_array)
@pytest.mark.parametrize("array_type", ["list", "array", "series"])
def test_safe_indexing_1d_scalar(array_type):
array = _convert_container([1, 2, 3, 4, 5, 6, 7, 8, 9], array_type)
indices = 2
subset = _safe_indexing(array, indices, axis=0)
assert subset == 3
@pytest.mark.parametrize(
"array_type, expected_output_type",
[("array", "array"), ("sparse", "sparse"), ("dataframe", "series")],
)
@pytest.mark.parametrize("indices", [2, "col_2"])
def test_safe_indexing_2d_scalar_axis_1(array_type, expected_output_type, indices):
columns_name = ["col_0", "col_1", "col_2"]
array = _convert_container(
[[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type, columns_name
)
if isinstance(indices, str) and array_type != "dataframe":
err_msg = (
"Specifying the columns using strings is only supported for dataframes"
)
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(array, indices, axis=1)
else:
subset = _safe_indexing(array, indices, axis=1)
expected_output = [3, 6, 9]
if expected_output_type == "sparse":
# sparse matrix are keeping the 2D shape
expected_output = [[3], [6], [9]]
expected_array = _convert_container(expected_output, expected_output_type)
assert_allclose_dense_sparse(subset, expected_array)
@pytest.mark.parametrize("array_type", ["list", "array", "sparse"])
def test_safe_indexing_None_axis_0(array_type):
X = _convert_container([[1, 2, 3], [4, 5, 6], [7, 8, 9]], array_type)
X_subset = _safe_indexing(X, None, axis=0)
assert_allclose_dense_sparse(X_subset, X)
def test_safe_indexing_pandas_no_matching_cols_error():
pd = pytest.importorskip("pandas")
err_msg = "No valid specification of the columns."
X = pd.DataFrame(X_toy)
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(X, [1.0], axis=1)
@pytest.mark.parametrize("axis", [None, 3])
def test_safe_indexing_error_axis(axis):
with pytest.raises(ValueError, match="'axis' should be either 0"):
_safe_indexing(X_toy, [0, 1], axis=axis)
@pytest.mark.parametrize("X_constructor", ["array", "series"])
def test_safe_indexing_1d_array_error(X_constructor):
# check that we are raising an error if the array-like passed is 1D and
# we try to index on the 2nd dimension
X = list(range(5))
if X_constructor == "array":
X_constructor = np.asarray(X)
elif X_constructor == "series":
pd = pytest.importorskip("pandas")
X_constructor = pd.Series(X)
err_msg = "'X' should be a 2D NumPy array, 2D sparse matrix or pandas"
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(X_constructor, [0, 1], axis=1)
def test_safe_indexing_container_axis_0_unsupported_type():
indices = ["col_1", "col_2"]
array = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
err_msg = "String indexing is not supported with 'axis=0'"
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(array, indices, axis=0)
def test_safe_indexing_pandas_no_settingwithcopy_warning():
# Using safe_indexing with an array-like indexer gives a copy of the
# DataFrame -> ensure it doesn't raise a warning if modified
pd = pytest.importorskip("pandas")
pd_version = parse_version(pd.__version__)
pd_base_version = parse_version(pd_version.base_version)
if pd_base_version >= parse_version("3"):
raise SkipTest("SettingWithCopyWarning has been removed in pandas 3.0.0.dev")
X = pd.DataFrame({"a": [1, 2, 3], "b": [3, 4, 5]})
subset = _safe_indexing(X, [0, 1], axis=0)
if hasattr(pd.errors, "SettingWithCopyWarning"):
SettingWithCopyWarning = pd.errors.SettingWithCopyWarning
else:
# backward compatibility for pandas < 1.5
SettingWithCopyWarning = pd.core.common.SettingWithCopyWarning
with warnings.catch_warnings():
warnings.simplefilter("error", SettingWithCopyWarning)
subset.iloc[0, 0] = 10
# The original dataframe is unaffected by the assignment on the subset:
assert X.iloc[0, 0] == 1
@pytest.mark.parametrize("indices", [0, [0, 1], slice(0, 2), np.array([0, 1])])
def test_safe_indexing_list_axis_1_unsupported(indices):
"""Check that we raise a ValueError when axis=1 with input as list."""
X = [[1, 2], [4, 5], [7, 8]]
err_msg = "axis=1 is not supported for lists"
with pytest.raises(ValueError, match=err_msg):
_safe_indexing(X, indices, axis=1)
@pytest.mark.parametrize(
"key, err_msg",
[
(10, r"all features must be in \[0, 2\]"),
("whatever", "A given column is not a column of the dataframe"),
(object(), "No valid specification of the columns"),
],
)
def test_get_column_indices_error(key, err_msg):
pd = pytest.importorskip("pandas")
X_df = pd.DataFrame(X_toy, columns=["col_0", "col_1", "col_2"])
with pytest.raises(ValueError, match=err_msg):
_get_column_indices(X_df, key)
@pytest.mark.parametrize(
"key", [["col1"], ["col2"], ["col1", "col2"], ["col1", "col3"], ["col2", "col3"]]
)
def test_get_column_indices_pandas_nonunique_columns_error(key):
pd = pytest.importorskip("pandas")
toy = np.zeros((1, 5), dtype=int)
columns = ["col1", "col1", "col2", "col3", "col2"]
X = pd.DataFrame(toy, columns=columns)
err_msg = "Selected columns, {}, are not unique in dataframe".format(key)
with pytest.raises(ValueError) as exc_info:
_get_column_indices(X, key)
assert str(exc_info.value) == err_msg
def test_shuffle_on_ndim_equals_three():
def to_tuple(A): # to make the inner arrays hashable
return tuple(tuple(tuple(C) for C in B) for B in A)
A = np.array([[[1, 2], [3, 4]], [[5, 6], [7, 8]]]) # A.shape = (2,2,2)
S = set(to_tuple(A))
shuffle(A) # shouldn't raise a ValueError for dim = 3
assert set(to_tuple(A)) == S
@pytest.mark.parametrize("csc_container", CSC_CONTAINERS)
def test_shuffle_dont_convert_to_array(csc_container):
# Check that shuffle does not try to convert to numpy arrays with float
# dtypes can let any indexable datastructure pass-through.
a = ["a", "b", "c"]
b = np.array(["a", "b", "c"], dtype=object)
c = [1, 2, 3]
d = MockDataFrame(np.array([["a", 0], ["b", 1], ["c", 2]], dtype=object))
e = csc_container(np.arange(6).reshape(3, 2))
a_s, b_s, c_s, d_s, e_s = shuffle(a, b, c, d, e, random_state=0)
assert a_s == ["c", "b", "a"]
assert type(a_s) == list # noqa: E721
assert_array_equal(b_s, ["c", "b", "a"])
assert b_s.dtype == object
assert c_s == [3, 2, 1]
assert type(c_s) == list # noqa: E721
assert_array_equal(d_s, np.array([["c", 2], ["b", 1], ["a", 0]], dtype=object))
assert type(d_s) == MockDataFrame # noqa: E721
assert_array_equal(e_s.toarray(), np.array([[4, 5], [2, 3], [0, 1]]))
def test_gen_even_slices():
# check that gen_even_slices contains all samples
some_range = range(10)
joined_range = list(chain(*[some_range[slice] for slice in gen_even_slices(10, 3)]))
assert_array_equal(some_range, joined_range)
@pytest.mark.parametrize(
("row_bytes", "max_n_rows", "working_memory", "expected"),
[
(1024, None, 1, 1024),
(1024, None, 0.99999999, 1023),
(1023, None, 1, 1025),
(1025, None, 1, 1023),
(1024, None, 2, 2048),
(1024, 7, 1, 7),
(1024 * 1024, None, 1, 1),
],
)
def test_get_chunk_n_rows(row_bytes, max_n_rows, working_memory, expected):
with warnings.catch_warnings():
warnings.simplefilter("error", UserWarning)
actual = get_chunk_n_rows(
row_bytes=row_bytes,
max_n_rows=max_n_rows,
working_memory=working_memory,
)
assert actual == expected
assert type(actual) is type(expected)
with config_context(working_memory=working_memory):
with warnings.catch_warnings():
warnings.simplefilter("error", UserWarning)
actual = get_chunk_n_rows(row_bytes=row_bytes, max_n_rows=max_n_rows)
assert actual == expected
assert type(actual) is type(expected)
def test_get_chunk_n_rows_warns():
"""Check that warning is raised when working_memory is too low."""
row_bytes = 1024 * 1024 + 1
max_n_rows = None
working_memory = 1
expected = 1
warn_msg = (
"Could not adhere to working_memory config. Currently 1MiB, 2MiB required."
)
with pytest.warns(UserWarning, match=warn_msg):
actual = get_chunk_n_rows(
row_bytes=row_bytes,
max_n_rows=max_n_rows,
working_memory=working_memory,
)
assert actual == expected
assert type(actual) is type(expected)
with config_context(working_memory=working_memory):
with pytest.warns(UserWarning, match=warn_msg):
actual = get_chunk_n_rows(row_bytes=row_bytes, max_n_rows=max_n_rows)
assert actual == expected
assert type(actual) is type(expected)
@pytest.mark.parametrize(
["source", "message", "is_long"],
[
("ABC", string.ascii_lowercase, False),
("ABCDEF", string.ascii_lowercase, False),
("ABC", string.ascii_lowercase * 3, True),
("ABC" * 10, string.ascii_lowercase, True),
("ABC", string.ascii_lowercase + "\u1048", False),
],
)
@pytest.mark.parametrize(
["time", "time_str"],
[
(0.2, " 0.2s"),
(20, " 20.0s"),
(2000, "33.3min"),
(20000, "333.3min"),
],
)
def test_message_with_time(source, message, is_long, time, time_str):
out = _message_with_time(source, message, time)
if is_long:
assert len(out) > 70
else:
assert len(out) == 70
assert out.startswith("[" + source + "] ")
out = out[len(source) + 3 :]
assert out.endswith(time_str)
out = out[: -len(time_str)]
assert out.endswith(", total=")
out = out[: -len(", total=")]
assert out.endswith(message)
out = out[: -len(message)]
assert out.endswith(" ")
out = out[:-1]
if is_long:
assert not out
else:
assert list(set(out)) == ["."]
@pytest.mark.parametrize(
["message", "expected"],
[
("hello", _message_with_time("ABC", "hello", 0.1) + "\n"),
("", _message_with_time("ABC", "", 0.1) + "\n"),
(None, ""),
],
)
def test_print_elapsed_time(message, expected, capsys, monkeypatch):
monkeypatch.setattr(timeit, "default_timer", lambda: 0)
with _print_elapsed_time("ABC", message):
monkeypatch.setattr(timeit, "default_timer", lambda: 0.1)
assert capsys.readouterr().out == expected
@pytest.mark.parametrize(
"value, result",
[
(float("nan"), True),
(np.nan, True),
(float(np.nan), True),
(np.float32(np.nan), True),
(np.float64(np.nan), True),
(0, False),
(0.0, False),
(None, False),
("", False),
("nan", False),
([np.nan], False),
(9867966753463435747313673, False), # Python int that overflows with C type
],
)
def test_is_scalar_nan(value, result):
assert is_scalar_nan(value) is result
# make sure that we are returning a Python bool
assert isinstance(is_scalar_nan(value), bool)
def test_approximate_mode():
"""Make sure sklearn.utils._approximate_mode returns valid
results for cases where "class_counts * n_draws" is enough
to overflow 32-bit signed integer.
Non-regression test for:
https://github.com/scikit-learn/scikit-learn/issues/20774
"""
X = np.array([99000, 1000], dtype=np.int32)
ret = _approximate_mode(class_counts=X, n_draws=25000, rng=0)
# Draws 25% of the total population, so in this case a fair draw means:
# 25% * 99.000 = 24.750
# 25% * 1.000 = 250
assert_array_equal(ret, [24750, 250])
def dummy_func():
pass
def test_deprecation_joblib_api(tmpdir):
# Only parallel_backend and register_parallel_backend are not deprecated in
# sklearn.utils
from sklearn.utils import parallel_backend, register_parallel_backend
assert_no_warnings(parallel_backend, "loky", None)
assert_no_warnings(register_parallel_backend, "failing", None)
from sklearn.utils._joblib import joblib
del joblib.parallel.BACKENDS["failing"]
@pytest.mark.parametrize("sequence", [[np.array(1), np.array(2)], [[1, 2], [3, 4]]])
def test_to_object_array(sequence):
out = _to_object_array(sequence)
assert isinstance(out, np.ndarray)
assert out.dtype.kind == "O"
assert out.ndim == 1
@pytest.mark.parametrize("array_type", ["array", "sparse", "dataframe"])
def test_safe_assign(array_type):
"""Check that `_safe_assign` works as expected."""
rng = np.random.RandomState(0)
X_array = rng.randn(10, 5)
row_indexer = [1, 2]
values = rng.randn(len(row_indexer), X_array.shape[1])
X = _convert_container(X_array, array_type)
_safe_assign(X, values, row_indexer=row_indexer)
assigned_portion = _safe_indexing(X, row_indexer, axis=0)
assert_allclose_dense_sparse(
assigned_portion, _convert_container(values, array_type)
)
column_indexer = [1, 2]
values = rng.randn(X_array.shape[0], len(column_indexer))
X = _convert_container(X_array, array_type)
_safe_assign(X, values, column_indexer=column_indexer)
assigned_portion = _safe_indexing(X, column_indexer, axis=1)
assert_allclose_dense_sparse(
assigned_portion, _convert_container(values, array_type)
)
row_indexer, column_indexer = None, None
values = rng.randn(*X.shape)
X = _convert_container(X_array, array_type)
_safe_assign(X, values, column_indexer=column_indexer)
assert_allclose_dense_sparse(X, _convert_container(values, array_type))
def test_get_column_indices_interchange():
"""Check _get_column_indices for edge cases with the interchange"""
pd = pytest.importorskip("pandas", minversion="1.5")
df = pd.DataFrame([[1, 2, 3], [4, 5, 6]], columns=["a", "b", "c"])
# Hide the fact that this is a pandas dataframe to trigger the dataframe protocol
# code path.
class MockDataFrame:
def __init__(self, df):
self._df = df
def __getattr__(self, name):
return getattr(self._df, name)
df_mocked = MockDataFrame(df)
key_results = [
(slice(1, None), [1, 2]),
(slice(None, 2), [0, 1]),
(slice(1, 2), [1]),
(["b", "c"], [1, 2]),
(slice("a", "b"), [0, 1]),
(slice("a", None), [0, 1, 2]),
(slice(None, "a"), [0]),
(["c", "a"], [2, 0]),
([], []),
]
for key, result in key_results:
assert _get_column_indices(df_mocked, key) == result
msg = "A given column is not a column of the dataframe"
with pytest.raises(ValueError, match=msg):
_get_column_indices(df_mocked, ["not_a_column"])
msg = "key.step must be 1 or None"
with pytest.raises(NotImplementedError, match=msg):
_get_column_indices(df_mocked, slice("a", None, 2))
def test_polars_indexing():
"""Check _safe_indexing for polars as expected."""
pl = pytest.importorskip("polars", minversion="0.18.2")
df = pl.DataFrame(
{"a": [1, 2, 3, 4], "b": [4, 5, 6, 8], "c": [1, 4, 1, 10]}, orient="row"
)
from polars.testing import assert_frame_equal
str_keys = [["b"], ["a", "b"], ["b", "a", "c"], ["c"], ["a"]]
for key in str_keys:
out = _safe_indexing(df, key, axis=1)
assert_frame_equal(df[key], out)
bool_keys = [([True, False, True], ["a", "c"]), ([False, False, True], ["c"])]
for bool_key, str_key in bool_keys:
out = _safe_indexing(df, bool_key, axis=1)
assert_frame_equal(df[:, str_key], out)
int_keys = [([0, 1], ["a", "b"]), ([2], ["c"])]
for int_key, str_key in int_keys:
out = _safe_indexing(df, int_key, axis=1)
assert_frame_equal(df[:, str_key], out)
axis_0_keys = [[0, 1], [1, 3], [3, 2]]
for key in axis_0_keys:
out = _safe_indexing(df, key, axis=0)
assert_frame_equal(df[key], out)
def test__is_polars_df():
"""Check that _is_polars_df return False for non-dataframe objects."""
class LooksLikePolars:
def __init__(self):
self.columns = ["a", "b"]
self.schema = ["a", "b"]
assert not _is_polars_df(LooksLikePolars())