projektAI/venv/Lib/site-packages/sklearn/neighbors/tests/test_ball_tree.py
2021-06-06 22:13:05 +02:00

86 lines
2.7 KiB
Python

import itertools
import numpy as np
import pytest
from numpy.testing import assert_array_almost_equal
from sklearn.neighbors._ball_tree import BallTree
from sklearn.neighbors import DistanceMetric
from sklearn.utils import check_random_state
from sklearn.utils.validation import check_array
from sklearn.utils._testing import _convert_container
rng = np.random.RandomState(10)
V_mahalanobis = rng.rand(3, 3)
V_mahalanobis = np.dot(V_mahalanobis, V_mahalanobis.T)
DIMENSION = 3
METRICS = {'euclidean': {},
'manhattan': {},
'minkowski': dict(p=3),
'chebyshev': {},
'seuclidean': dict(V=rng.random_sample(DIMENSION)),
'wminkowski': dict(p=3, w=rng.random_sample(DIMENSION)),
'mahalanobis': dict(V=V_mahalanobis)}
DISCRETE_METRICS = ['hamming',
'canberra',
'braycurtis']
BOOLEAN_METRICS = ['matching', 'jaccard', 'dice', 'kulsinski',
'rogerstanimoto', 'russellrao', 'sokalmichener',
'sokalsneath']
def brute_force_neighbors(X, Y, k, metric, **kwargs):
X, Y = check_array(X), check_array(Y)
D = DistanceMetric.get_metric(metric, **kwargs).pairwise(Y, X)
ind = np.argsort(D, axis=1)[:, :k]
dist = D[np.arange(Y.shape[0])[:, None], ind]
return dist, ind
@pytest.mark.parametrize(
'metric',
itertools.chain(BOOLEAN_METRICS, DISCRETE_METRICS)
)
@pytest.mark.parametrize("array_type", ["list", "array"])
def test_ball_tree_query_metrics(metric, array_type):
rng = check_random_state(0)
if metric in BOOLEAN_METRICS:
X = rng.random_sample((40, 10)).round(0)
Y = rng.random_sample((10, 10)).round(0)
elif metric in DISCRETE_METRICS:
X = (4 * rng.random_sample((40, 10))).round(0)
Y = (4 * rng.random_sample((10, 10))).round(0)
X = _convert_container(X, array_type)
Y = _convert_container(Y, array_type)
k = 5
bt = BallTree(X, leaf_size=1, metric=metric)
dist1, ind1 = bt.query(Y, k)
dist2, ind2 = brute_force_neighbors(X, Y, k, metric)
assert_array_almost_equal(dist1, dist2)
def test_query_haversine():
rng = check_random_state(0)
X = 2 * np.pi * rng.random_sample((40, 2))
bt = BallTree(X, leaf_size=1, metric='haversine')
dist1, ind1 = bt.query(X, k=5)
dist2, ind2 = brute_force_neighbors(X, X, k=5, metric='haversine')
assert_array_almost_equal(dist1, dist2)
assert_array_almost_equal(ind1, ind2)
def test_array_object_type():
"""Check that we do not accept object dtype array."""
X = np.array([(1, 2, 3), (2, 5), (5, 5, 1, 2)], dtype=object)
with pytest.raises(
ValueError,
match="setting an array element with a sequence"
):
BallTree(X)