scikit-learn/sklearn/utils/tests/test_utils.py

321 lines
11 KiB
Python

from itertools import chain, product
import warnings
import pytest
import numpy as np
import scipy.sparse as sp
from sklearn.utils.testing import (assert_equal, assert_raises,
assert_array_equal,
SkipTest, assert_raises_regex,
assert_warns_message, assert_no_warnings)
from sklearn.utils import check_random_state
from sklearn.utils import deprecated
from sklearn.utils import resample
from sklearn.utils import safe_mask
from sklearn.utils import column_or_1d
from sklearn.utils import safe_indexing
from sklearn.utils import shuffle
from sklearn.utils import gen_even_slices
from sklearn.utils import get_chunk_n_rows
from sklearn.utils import is_scalar_nan
from sklearn.utils.mocking import MockDataFrame
from sklearn import config_context
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)
assert_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_equal(spam, "spam") # function must remain usable
assert_equal(len(w), 1)
assert issubclass(w[0].category, DeprecationWarning)
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(object):
SPAM = 1
ham = Ham()
assert hasattr(ham, "SPAM")
assert_equal(len(w), 1)
assert issubclass(w[0].category, DeprecationWarning)
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
assert_raises(ValueError, resample, [0], [0, 1])
assert_raises(ValueError, resample, [0, 1], [0, 1],
replace=False, n_samples=3)
assert_raises(ValueError, resample, [0, 1], [0, 1], meaning_of_life=42)
# Issue:6581, n_samples can be more when replace is True (default).
assert_equal(len(resample([1, 2], n_samples=5)), 5)
def test_safe_mask():
random_state = check_random_state(0)
X = random_state.rand(5, 4)
X_csr = sp.csr_matrix(X)
mask = [False, False, True, True, True]
mask = safe_mask(X, mask)
assert_equal(X[mask].shape[0], 3)
mask = safe_mask(X_csr, mask)
assert_equal(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.),
("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:
assert_raises(ValueError, column_or_1d, y)
def test_safe_indexing():
X = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
inds = np.array([1, 2])
X_inds = safe_indexing(X, inds)
X_arrays = safe_indexing(np.array(X), inds)
assert_array_equal(np.array(X_inds), X_arrays)
assert_array_equal(np.array(X_inds), np.array(X)[inds])
def test_safe_indexing_pandas():
try:
import pandas as pd
except ImportError:
raise SkipTest("Pandas not found")
X = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
X_df = pd.DataFrame(X)
inds = np.array([1, 2])
X_df_indexed = safe_indexing(X_df, inds)
X_indexed = safe_indexing(X_df, inds)
assert_array_equal(np.array(X_df_indexed), X_indexed)
# fun with read-only data in dataframes
# this happens in joblib memmapping
X.setflags(write=False)
X_df_readonly = pd.DataFrame(X)
inds_readonly = inds.copy()
inds_readonly.setflags(write=False)
for this_df, this_inds in product([X_df, X_df_readonly],
[inds, inds_readonly]):
with warnings.catch_warnings(record=True):
X_df_indexed = safe_indexing(this_df, this_inds)
assert_array_equal(np.array(X_df_indexed), X_indexed)
def test_safe_indexing_mock_pandas():
X = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
X_df = MockDataFrame(X)
inds = np.array([1, 2])
X_df_indexed = safe_indexing(X_df, inds)
X_indexed = safe_indexing(X_df, inds)
assert_array_equal(np.array(X_df_indexed), X_indexed)
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_equal(set(to_tuple(A)), S)
def test_shuffle_dont_convert_to_array():
# 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 = sp.csc_matrix(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_equal(a_s, ['c', 'b', 'a'])
assert_equal(type(a_s), list)
assert_array_equal(b_s, ['c', 'b', 'a'])
assert_equal(b_s.dtype, object)
assert_equal(c_s, [3, 2, 1])
assert_equal(type(c_s), list)
assert_array_equal(d_s, np.array([['c', 2],
['b', 1],
['a', 0]],
dtype=object))
assert_equal(type(d_s), MockDataFrame)
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)
# check that passing negative n_chunks raises an error
slices = gen_even_slices(10, -1)
assert_raises_regex(ValueError, "gen_even_slices got n_packs=-1, must be"
" >=1", next, slices)
@pytest.mark.parametrize(
('row_bytes', 'max_n_rows', 'working_memory', 'expected', 'warning'),
[(1024, None, 1, 1024, None),
(1024, None, 0.99999999, 1023, None),
(1023, None, 1, 1025, None),
(1025, None, 1, 1023, None),
(1024, None, 2, 2048, None),
(1024, 7, 1, 7, None),
(1024 * 1024, None, 1, 1, None),
(1024 * 1024 + 1, None, 1, 1,
'Could not adhere to working_memory config. '
'Currently 1MiB, 2MiB required.'),
])
def test_get_chunk_n_rows(row_bytes, max_n_rows, working_memory,
expected, warning):
if warning is not None:
def check_warning(*args, **kw):
return assert_warns_message(UserWarning, warning, *args, **kw)
else:
check_warning = assert_no_warnings
actual = check_warning(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):
actual = check_warning(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("value, result", [(float("nan"), True),
(np.nan, True),
(np.float("nan"), True),
(np.float32("nan"), True),
(np.float64("nan"), True),
(0, False),
(0., False),
(None, False),
("", False),
("nan", False),
([np.nan], False)])
def test_is_scalar_nan(value, result):
assert is_scalar_nan(value) is result
def dummy_func():
pass
def test_deprecation_joblib_api(tmpdir):
def check_warning(*args, **kw):
return assert_warns_message(
DeprecationWarning, "deprecated in version 0.20.1", *args, **kw)
# Ensure that the joblib API is deprecated in sklearn.util
from sklearn.utils import Parallel, Memory, delayed
from sklearn.utils import cpu_count, hash, effective_n_jobs
check_warning(Memory, str(tmpdir))
check_warning(hash, 1)
check_warning(Parallel)
check_warning(cpu_count)
check_warning(effective_n_jobs, 1)
check_warning(delayed, dummy_func)
# 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)
# Ensure that the deprecation have no side effect in sklearn.utils._joblib
from sklearn.utils._joblib import Parallel, Memory, delayed
from sklearn.utils._joblib import cpu_count, hash, effective_n_jobs
from sklearn.utils._joblib import parallel_backend
from sklearn.utils._joblib import register_parallel_backend
assert_no_warnings(Memory, str(tmpdir))
assert_no_warnings(hash, 1)
assert_no_warnings(Parallel)
assert_no_warnings(cpu_count)
assert_no_warnings(effective_n_jobs, 1)
assert_no_warnings(delayed, dummy_func)
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']