Inzynierka/Lib/site-packages/sklearn/metrics/cluster/tests/test_common.py
2023-06-02 12:51:02 +02:00

220 lines
7.9 KiB
Python

from functools import partial
from itertools import chain
import pytest
import numpy as np
from sklearn.metrics.cluster import adjusted_mutual_info_score
from sklearn.metrics.cluster import adjusted_rand_score
from sklearn.metrics.cluster import rand_score
from sklearn.metrics.cluster import completeness_score
from sklearn.metrics.cluster import fowlkes_mallows_score
from sklearn.metrics.cluster import homogeneity_score
from sklearn.metrics.cluster import mutual_info_score
from sklearn.metrics.cluster import normalized_mutual_info_score
from sklearn.metrics.cluster import v_measure_score
from sklearn.metrics.cluster import silhouette_score
from sklearn.metrics.cluster import calinski_harabasz_score
from sklearn.metrics.cluster import davies_bouldin_score
from sklearn.utils._testing import assert_allclose
# Dictionaries of metrics
# ------------------------
# The goal of having those dictionaries is to have an easy way to call a
# particular metric and associate a name to each function:
# - SUPERVISED_METRICS: all supervised cluster metrics - (when given a
# ground truth value)
# - UNSUPERVISED_METRICS: all unsupervised cluster metrics
#
# Those dictionaries will be used to test systematically some invariance
# properties, e.g. invariance toward several input layout.
#
SUPERVISED_METRICS = {
"adjusted_mutual_info_score": adjusted_mutual_info_score,
"adjusted_rand_score": adjusted_rand_score,
"rand_score": rand_score,
"completeness_score": completeness_score,
"homogeneity_score": homogeneity_score,
"mutual_info_score": mutual_info_score,
"normalized_mutual_info_score": normalized_mutual_info_score,
"v_measure_score": v_measure_score,
"fowlkes_mallows_score": fowlkes_mallows_score,
}
UNSUPERVISED_METRICS = {
"silhouette_score": silhouette_score,
"silhouette_manhattan": partial(silhouette_score, metric="manhattan"),
"calinski_harabasz_score": calinski_harabasz_score,
"davies_bouldin_score": davies_bouldin_score,
}
# Lists of metrics with common properties
# ---------------------------------------
# Lists of metrics with common properties are used to test systematically some
# functionalities and invariance, e.g. SYMMETRIC_METRICS lists all metrics
# that are symmetric with respect to their input argument y_true and y_pred.
#
# --------------------------------------------------------------------
# Symmetric with respect to their input arguments y_true and y_pred.
# Symmetric metrics only apply to supervised clusters.
SYMMETRIC_METRICS = [
"adjusted_rand_score",
"rand_score",
"v_measure_score",
"mutual_info_score",
"adjusted_mutual_info_score",
"normalized_mutual_info_score",
"fowlkes_mallows_score",
]
NON_SYMMETRIC_METRICS = ["homogeneity_score", "completeness_score"]
# Metrics whose upper bound is 1
NORMALIZED_METRICS = [
"adjusted_rand_score",
"rand_score",
"homogeneity_score",
"completeness_score",
"v_measure_score",
"adjusted_mutual_info_score",
"fowlkes_mallows_score",
"normalized_mutual_info_score",
]
rng = np.random.RandomState(0)
y1 = rng.randint(3, size=30)
y2 = rng.randint(3, size=30)
def test_symmetric_non_symmetric_union():
assert sorted(SYMMETRIC_METRICS + NON_SYMMETRIC_METRICS) == sorted(
SUPERVISED_METRICS
)
# 0.22 AMI and NMI changes
@pytest.mark.filterwarnings("ignore::FutureWarning")
@pytest.mark.parametrize(
"metric_name, y1, y2", [(name, y1, y2) for name in SYMMETRIC_METRICS]
)
def test_symmetry(metric_name, y1, y2):
metric = SUPERVISED_METRICS[metric_name]
assert metric(y1, y2) == pytest.approx(metric(y2, y1))
@pytest.mark.parametrize(
"metric_name, y1, y2", [(name, y1, y2) for name in NON_SYMMETRIC_METRICS]
)
def test_non_symmetry(metric_name, y1, y2):
metric = SUPERVISED_METRICS[metric_name]
assert metric(y1, y2) != pytest.approx(metric(y2, y1))
# 0.22 AMI and NMI changes
@pytest.mark.filterwarnings("ignore::FutureWarning")
@pytest.mark.parametrize("metric_name", NORMALIZED_METRICS)
def test_normalized_output(metric_name):
upper_bound_1 = [0, 0, 0, 1, 1, 1]
upper_bound_2 = [0, 0, 0, 1, 1, 1]
metric = SUPERVISED_METRICS[metric_name]
assert metric([0, 0, 0, 1, 1], [0, 0, 0, 1, 2]) > 0.0
assert metric([0, 0, 1, 1, 2], [0, 0, 1, 1, 1]) > 0.0
assert metric([0, 0, 0, 1, 2], [0, 1, 1, 1, 1]) < 1.0
assert metric([0, 0, 0, 1, 2], [0, 1, 1, 1, 1]) < 1.0
assert metric(upper_bound_1, upper_bound_2) == pytest.approx(1.0)
lower_bound_1 = [0, 0, 0, 0, 0, 0]
lower_bound_2 = [0, 1, 2, 3, 4, 5]
score = np.array(
[metric(lower_bound_1, lower_bound_2), metric(lower_bound_2, lower_bound_1)]
)
assert not (score < 0).any()
# 0.22 AMI and NMI changes
@pytest.mark.filterwarnings("ignore::FutureWarning")
@pytest.mark.parametrize("metric_name", chain(SUPERVISED_METRICS, UNSUPERVISED_METRICS))
def test_permute_labels(metric_name):
# All clustering metrics do not change score due to permutations of labels
# that is when 0 and 1 exchanged.
y_label = np.array([0, 0, 0, 1, 1, 0, 1])
y_pred = np.array([1, 0, 1, 0, 1, 1, 0])
if metric_name in SUPERVISED_METRICS:
metric = SUPERVISED_METRICS[metric_name]
score_1 = metric(y_pred, y_label)
assert_allclose(score_1, metric(1 - y_pred, y_label))
assert_allclose(score_1, metric(1 - y_pred, 1 - y_label))
assert_allclose(score_1, metric(y_pred, 1 - y_label))
else:
metric = UNSUPERVISED_METRICS[metric_name]
X = np.random.randint(10, size=(7, 10))
score_1 = metric(X, y_pred)
assert_allclose(score_1, metric(X, 1 - y_pred))
# 0.22 AMI and NMI changes
@pytest.mark.filterwarnings("ignore::FutureWarning")
@pytest.mark.parametrize("metric_name", chain(SUPERVISED_METRICS, UNSUPERVISED_METRICS))
# For all clustering metrics Input parameters can be both
# in the form of arrays lists, positive, negative or string
def test_format_invariance(metric_name):
y_true = [0, 0, 0, 0, 1, 1, 1, 1]
y_pred = [0, 1, 2, 3, 4, 5, 6, 7]
def generate_formats(y):
y = np.array(y)
yield y, "array of ints"
yield y.tolist(), "list of ints"
yield [str(x) + "-a" for x in y.tolist()], "list of strs"
yield (
np.array([str(x) + "-a" for x in y.tolist()], dtype=object),
"array of strs",
)
yield y - 1, "including negative ints"
yield y + 1, "strictly positive ints"
if metric_name in SUPERVISED_METRICS:
metric = SUPERVISED_METRICS[metric_name]
score_1 = metric(y_true, y_pred)
y_true_gen = generate_formats(y_true)
y_pred_gen = generate_formats(y_pred)
for (y_true_fmt, fmt_name), (y_pred_fmt, _) in zip(y_true_gen, y_pred_gen):
assert score_1 == metric(y_true_fmt, y_pred_fmt)
else:
metric = UNSUPERVISED_METRICS[metric_name]
X = np.random.randint(10, size=(8, 10))
score_1 = metric(X, y_true)
assert score_1 == metric(X.astype(float), y_true)
y_true_gen = generate_formats(y_true)
for y_true_fmt, fmt_name in y_true_gen:
assert score_1 == metric(X, y_true_fmt)
@pytest.mark.parametrize("metric", SUPERVISED_METRICS.values())
def test_single_sample(metric):
# only the supervised metrics support single sample
for i, j in [(0, 0), (0, 1), (1, 0), (1, 1)]:
metric([i], [j])
@pytest.mark.parametrize(
"metric_name, metric_func", dict(SUPERVISED_METRICS, **UNSUPERVISED_METRICS).items()
)
def test_inf_nan_input(metric_name, metric_func):
if metric_name in SUPERVISED_METRICS:
invalids = [
([0, 1], [np.inf, np.inf]),
([0, 1], [np.nan, np.nan]),
([0, 1], [np.nan, np.inf]),
]
else:
X = np.random.randint(10, size=(2, 10))
invalids = [(X, [np.inf, np.inf]), (X, [np.nan, np.nan]), (X, [np.nan, np.inf])]
with pytest.raises(ValueError, match=r"contains (NaN|infinity)"):
for args in invalids:
metric_func(*args)