projektAI/venv/Lib/site-packages/sklearn/svm/tests/test_sparse.py

363 lines
14 KiB
Python
Raw Normal View History

2021-06-06 22:13:05 +02:00
import pytest
import numpy as np
from numpy.testing import assert_array_almost_equal, assert_array_equal
from scipy import sparse
from sklearn import datasets, svm, linear_model, base
from sklearn.datasets import make_classification, load_digits, make_blobs
from sklearn.svm.tests import test_svm
from sklearn.exceptions import ConvergenceWarning
from sklearn.utils.extmath import safe_sparse_dot
from sklearn.utils._testing import (assert_warns,
assert_raise_message, ignore_warnings,
skip_if_32bit)
# test sample 1
X = np.array([[-2, -1], [-1, -1], [-1, -2], [1, 1], [1, 2], [2, 1]])
X_sp = sparse.lil_matrix(X)
Y = [1, 1, 1, 2, 2, 2]
T = np.array([[-1, -1], [2, 2], [3, 2]])
true_result = [1, 2, 2]
# test sample 2
X2 = np.array([[0, 0, 0], [1, 1, 1], [2, 0, 0, ],
[0, 0, 2], [3, 3, 3]])
X2_sp = sparse.dok_matrix(X2)
Y2 = [1, 2, 2, 2, 3]
T2 = np.array([[-1, -1, -1], [1, 1, 1], [2, 2, 2]])
true_result2 = [1, 2, 3]
iris = datasets.load_iris()
# permute
rng = np.random.RandomState(0)
perm = rng.permutation(iris.target.size)
iris.data = iris.data[perm]
iris.target = iris.target[perm]
# sparsify
iris.data = sparse.csr_matrix(iris.data)
def check_svm_model_equal(dense_svm, sparse_svm, X_train, y_train, X_test):
dense_svm.fit(X_train.toarray(), y_train)
if sparse.isspmatrix(X_test):
X_test_dense = X_test.toarray()
else:
X_test_dense = X_test
sparse_svm.fit(X_train, y_train)
assert sparse.issparse(sparse_svm.support_vectors_)
assert sparse.issparse(sparse_svm.dual_coef_)
assert_array_almost_equal(dense_svm.support_vectors_,
sparse_svm.support_vectors_.toarray())
assert_array_almost_equal(dense_svm.dual_coef_,
sparse_svm.dual_coef_.toarray())
if dense_svm.kernel == "linear":
assert sparse.issparse(sparse_svm.coef_)
assert_array_almost_equal(dense_svm.coef_, sparse_svm.coef_.toarray())
assert_array_almost_equal(dense_svm.support_, sparse_svm.support_)
assert_array_almost_equal(dense_svm.predict(X_test_dense),
sparse_svm.predict(X_test))
assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
sparse_svm.decision_function(X_test))
assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
sparse_svm.decision_function(X_test_dense))
if isinstance(dense_svm, svm.OneClassSVM):
msg = "cannot use sparse input in 'OneClassSVM' trained on dense data"
else:
assert_array_almost_equal(dense_svm.predict_proba(X_test_dense),
sparse_svm.predict_proba(X_test), 4)
msg = "cannot use sparse input in 'SVC' trained on dense data"
if sparse.isspmatrix(X_test):
assert_raise_message(ValueError, msg, dense_svm.predict, X_test)
@skip_if_32bit
def test_svc():
"""Check that sparse SVC gives the same result as SVC"""
# many class dataset:
X_blobs, y_blobs = make_blobs(n_samples=100, centers=10, random_state=0)
X_blobs = sparse.csr_matrix(X_blobs)
datasets = [[X_sp, Y, T], [X2_sp, Y2, T2],
[X_blobs[:80], y_blobs[:80], X_blobs[80:]],
[iris.data, iris.target, iris.data]]
kernels = ["linear", "poly", "rbf", "sigmoid"]
for dataset in datasets:
for kernel in kernels:
clf = svm.SVC(gamma=1, kernel=kernel, probability=True,
random_state=0, decision_function_shape='ovo')
sp_clf = svm.SVC(gamma=1, kernel=kernel, probability=True,
random_state=0, decision_function_shape='ovo')
check_svm_model_equal(clf, sp_clf, *dataset)
def test_unsorted_indices():
# test that the result with sorted and unsorted indices in csr is the same
# we use a subset of digits as iris, blobs or make_classification didn't
# show the problem
X, y = load_digits(return_X_y=True)
X_test = sparse.csr_matrix(X[50:100])
X, y = X[:50], y[:50]
X_sparse = sparse.csr_matrix(X)
coef_dense = svm.SVC(kernel='linear', probability=True,
random_state=0).fit(X, y).coef_
sparse_svc = svm.SVC(kernel='linear', probability=True,
random_state=0).fit(X_sparse, y)
coef_sorted = sparse_svc.coef_
# make sure dense and sparse SVM give the same result
assert_array_almost_equal(coef_dense, coef_sorted.toarray())
# reverse each row's indices
def scramble_indices(X):
new_data = []
new_indices = []
for i in range(1, len(X.indptr)):
row_slice = slice(*X.indptr[i - 1: i + 1])
new_data.extend(X.data[row_slice][::-1])
new_indices.extend(X.indices[row_slice][::-1])
return sparse.csr_matrix((new_data, new_indices, X.indptr),
shape=X.shape)
X_sparse_unsorted = scramble_indices(X_sparse)
X_test_unsorted = scramble_indices(X_test)
assert not X_sparse_unsorted.has_sorted_indices
assert not X_test_unsorted.has_sorted_indices
unsorted_svc = svm.SVC(kernel='linear', probability=True,
random_state=0).fit(X_sparse_unsorted, y)
coef_unsorted = unsorted_svc.coef_
# make sure unsorted indices give same result
assert_array_almost_equal(coef_unsorted.toarray(), coef_sorted.toarray())
assert_array_almost_equal(sparse_svc.predict_proba(X_test_unsorted),
sparse_svc.predict_proba(X_test))
def test_svc_with_custom_kernel():
def kfunc(x, y):
return safe_sparse_dot(x, y.T)
clf_lin = svm.SVC(kernel='linear').fit(X_sp, Y)
clf_mylin = svm.SVC(kernel=kfunc).fit(X_sp, Y)
assert_array_equal(clf_lin.predict(X_sp), clf_mylin.predict(X_sp))
def test_svc_iris():
# Test the sparse SVC with the iris dataset
for k in ('linear', 'poly', 'rbf'):
sp_clf = svm.SVC(kernel=k).fit(iris.data, iris.target)
clf = svm.SVC(kernel=k).fit(iris.data.toarray(),
iris.target)
assert_array_almost_equal(clf.support_vectors_,
sp_clf.support_vectors_.toarray())
assert_array_almost_equal(clf.dual_coef_, sp_clf.dual_coef_.toarray())
assert_array_almost_equal(
clf.predict(iris.data.toarray()), sp_clf.predict(iris.data))
if k == 'linear':
assert_array_almost_equal(clf.coef_, sp_clf.coef_.toarray())
def test_sparse_decision_function():
# Test decision_function
# Sanity check, test that decision_function implemented in python
# returns the same as the one in libsvm
# multi class:
svc = svm.SVC(kernel='linear', C=0.1, decision_function_shape='ovo')
clf = svc.fit(iris.data, iris.target)
dec = safe_sparse_dot(iris.data, clf.coef_.T) + clf.intercept_
assert_array_almost_equal(dec, clf.decision_function(iris.data))
# binary:
clf.fit(X, Y)
dec = np.dot(X, clf.coef_.T) + clf.intercept_
prediction = clf.predict(X)
assert_array_almost_equal(dec.ravel(), clf.decision_function(X))
assert_array_almost_equal(
prediction,
clf.classes_[(clf.decision_function(X) > 0).astype(int).ravel()])
expected = np.array([-1., -0.66, -1., 0.66, 1., 1.])
assert_array_almost_equal(clf.decision_function(X), expected, 2)
def test_error():
# Test that it gives proper exception on deficient input
# impossible value of C
with pytest.raises(ValueError):
svm.SVC(C=-1).fit(X, Y)
# impossible value of nu
clf = svm.NuSVC(nu=0.0)
with pytest.raises(ValueError):
clf.fit(X_sp, Y)
Y2 = Y[:-1] # wrong dimensions for labels
with pytest.raises(ValueError):
clf.fit(X_sp, Y2)
clf = svm.SVC()
clf.fit(X_sp, Y)
assert_array_equal(clf.predict(T), true_result)
def test_linearsvc():
# Similar to test_SVC
clf = svm.LinearSVC(random_state=0).fit(X, Y)
sp_clf = svm.LinearSVC(random_state=0).fit(X_sp, Y)
assert sp_clf.fit_intercept
assert_array_almost_equal(clf.coef_, sp_clf.coef_, decimal=4)
assert_array_almost_equal(clf.intercept_, sp_clf.intercept_, decimal=4)
assert_array_almost_equal(clf.predict(X), sp_clf.predict(X_sp))
clf.fit(X2, Y2)
sp_clf.fit(X2_sp, Y2)
assert_array_almost_equal(clf.coef_, sp_clf.coef_, decimal=4)
assert_array_almost_equal(clf.intercept_, sp_clf.intercept_, decimal=4)
def test_linearsvc_iris():
# Test the sparse LinearSVC with the iris dataset
sp_clf = svm.LinearSVC(random_state=0).fit(iris.data, iris.target)
clf = svm.LinearSVC(random_state=0).fit(iris.data.toarray(), iris.target)
assert clf.fit_intercept == sp_clf.fit_intercept
assert_array_almost_equal(clf.coef_, sp_clf.coef_, decimal=1)
assert_array_almost_equal(clf.intercept_, sp_clf.intercept_, decimal=1)
assert_array_almost_equal(
clf.predict(iris.data.toarray()), sp_clf.predict(iris.data))
# check decision_function
pred = np.argmax(sp_clf.decision_function(iris.data), 1)
assert_array_almost_equal(pred, clf.predict(iris.data.toarray()))
# sparsify the coefficients on both models and check that they still
# produce the same results
clf.sparsify()
assert_array_equal(pred, clf.predict(iris.data))
sp_clf.sparsify()
assert_array_equal(pred, sp_clf.predict(iris.data))
def test_weight():
# Test class weights
X_, y_ = make_classification(n_samples=200, n_features=100,
weights=[0.833, 0.167], random_state=0)
X_ = sparse.csr_matrix(X_)
for clf in (linear_model.LogisticRegression(),
svm.LinearSVC(random_state=0),
svm.SVC()):
clf.set_params(class_weight={0: 5})
clf.fit(X_[:180], y_[:180])
y_pred = clf.predict(X_[180:])
assert np.sum(y_pred == y_[180:]) >= 11
def test_sample_weights():
# Test weights on individual samples
clf = svm.SVC()
clf.fit(X_sp, Y)
assert_array_equal(clf.predict([X[2]]), [1.])
sample_weight = [.1] * 3 + [10] * 3
clf.fit(X_sp, Y, sample_weight=sample_weight)
assert_array_equal(clf.predict([X[2]]), [2.])
def test_sparse_liblinear_intercept_handling():
# Test that sparse liblinear honours intercept_scaling param
test_svm.test_dense_liblinear_intercept_handling(svm.LinearSVC)
@pytest.mark.parametrize("datasets_index", range(4))
@pytest.mark.parametrize("kernel", ["linear", "poly", "rbf", "sigmoid"])
@skip_if_32bit
def test_sparse_oneclasssvm(datasets_index, kernel):
# Check that sparse OneClassSVM gives the same result as dense OneClassSVM
# many class dataset:
X_blobs, _ = make_blobs(n_samples=100, centers=10, random_state=0)
X_blobs = sparse.csr_matrix(X_blobs)
datasets = [[X_sp, None, T], [X2_sp, None, T2],
[X_blobs[:80], None, X_blobs[80:]],
[iris.data, None, iris.data]]
dataset = datasets[datasets_index]
clf = svm.OneClassSVM(gamma=1, kernel=kernel)
sp_clf = svm.OneClassSVM(gamma=1, kernel=kernel)
check_svm_model_equal(clf, sp_clf, *dataset)
def test_sparse_realdata():
# Test on a subset from the 20newsgroups dataset.
# This catches some bugs if input is not correctly converted into
# sparse format or weights are not correctly initialized.
data = np.array([0.03771744, 0.1003567, 0.01174647, 0.027069])
indices = np.array([6, 5, 35, 31])
indptr = np.array(
[0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4])
X = sparse.csr_matrix((data, indices, indptr))
y = np.array(
[1., 0., 2., 2., 1., 1., 1., 2., 2., 0., 1., 2., 2.,
0., 2., 0., 3., 0., 3., 0., 1., 1., 3., 2., 3., 2.,
0., 3., 1., 0., 2., 1., 2., 0., 1., 0., 2., 3., 1.,
3., 0., 1., 0., 0., 2., 0., 1., 2., 2., 2., 3., 2.,
0., 3., 2., 1., 2., 3., 2., 2., 0., 1., 0., 1., 2.,
3., 0., 0., 2., 2., 1., 3., 1., 1., 0., 1., 2., 1.,
1., 3.])
clf = svm.SVC(kernel='linear').fit(X.toarray(), y)
sp_clf = svm.SVC(kernel='linear').fit(sparse.coo_matrix(X), y)
assert_array_equal(clf.support_vectors_, sp_clf.support_vectors_.toarray())
assert_array_equal(clf.dual_coef_, sp_clf.dual_coef_.toarray())
def test_sparse_svc_clone_with_callable_kernel():
# Test that the "dense_fit" is called even though we use sparse input
# meaning that everything works fine.
a = svm.SVC(C=1, kernel=lambda x, y: x * y.T,
probability=True, random_state=0)
b = base.clone(a)
b.fit(X_sp, Y)
pred = b.predict(X_sp)
b.predict_proba(X_sp)
dense_svm = svm.SVC(C=1, kernel=lambda x, y: np.dot(x, y.T),
probability=True, random_state=0)
pred_dense = dense_svm.fit(X, Y).predict(X)
assert_array_equal(pred_dense, pred)
# b.decision_function(X_sp) # XXX : should be supported
def test_timeout():
sp = svm.SVC(C=1, kernel=lambda x, y: x * y.T,
probability=True, random_state=0, max_iter=1)
assert_warns(ConvergenceWarning, sp.fit, X_sp, Y)
def test_consistent_proba():
a = svm.SVC(probability=True, max_iter=1, random_state=0)
with ignore_warnings(category=ConvergenceWarning):
proba_1 = a.fit(X, Y).predict_proba(X)
a = svm.SVC(probability=True, max_iter=1, random_state=0)
with ignore_warnings(category=ConvergenceWarning):
proba_2 = a.fit(X, Y).predict_proba(X)
assert_array_almost_equal(proba_1, proba_2)