Exemple #1
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def test_predict_proba_multiclass():
    # Test that predict_proba works as expected for multi class.
    X = X_digits_multi[:10]
    y = y_digits_multi[:10]

    clf = MLPClassifier(hidden_layer_sizes=5)
    with ignore_warnings(category=ConvergenceWarning):
        clf.fit(X, y)
    y_proba = clf.predict_proba(X)
    y_log_proba = clf.predict_log_proba(X)

    (n_samples, n_classes) = y.shape[0], np.unique(y).size

    proba_max = y_proba.argmax(axis=1)
    proba_log_max = y_log_proba.argmax(axis=1)

    assert y_proba.shape == (n_samples, n_classes)
    assert_array_equal(proba_max, proba_log_max)
    assert_array_equal(y_log_proba, np.log(y_proba))
Exemple #2
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def test_predict_proba_multilabel():
    # Test that predict_proba works as expected for multilabel.
    # Multilabel should not use softmax which makes probabilities sum to 1
    X, Y = make_multilabel_classification(n_samples=50,
                                          random_state=0,
                                          return_indicator=True)
    n_samples, n_classes = Y.shape

    clf = MLPClassifier(solver='lbfgs', hidden_layer_sizes=30, random_state=0)
    clf.fit(X, Y)
    y_proba = clf.predict_proba(X)

    assert y_proba.shape == (n_samples, n_classes)
    assert_array_equal(y_proba > 0.5, Y)

    y_log_proba = clf.predict_log_proba(X)
    proba_max = y_proba.argmax(axis=1)
    proba_log_max = y_log_proba.argmax(axis=1)

    assert (y_proba.sum(1) - 1).dot(y_proba.sum(1) - 1) > 1e-10
    assert_array_equal(proba_max, proba_log_max)
    assert_array_equal(y_log_proba, np.log(y_proba))
Exemple #3
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def test_predict_proba_binary():
    # Test that predict_proba works as expected for binary class.
    X = X_digits_binary[:50]
    y = y_digits_binary[:50]

    clf = MLPClassifier(hidden_layer_sizes=5,
                        activation='logistic',
                        random_state=1)
    with ignore_warnings(category=ConvergenceWarning):
        clf.fit(X, y)
    y_proba = clf.predict_proba(X)
    y_log_proba = clf.predict_log_proba(X)

    (n_samples, n_classes) = y.shape[0], 2

    proba_max = y_proba.argmax(axis=1)
    proba_log_max = y_log_proba.argmax(axis=1)

    assert y_proba.shape == (n_samples, n_classes)
    assert_array_equal(proba_max, proba_log_max)
    assert_array_equal(y_log_proba, np.log(y_proba))

    assert roc_auc_score(y, y_proba[:, 1]) == 1.0