Ejemplo n.º 1
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def test_bagging_classifier_with_missing_inputs():
    # Check that BaggingClassifier can accept X with missing/infinite data
    X = np.array([
        [1, 3, 5],
        [2, None, 6],
        [2, np.nan, 6],
        [2, np.inf, 6],
        [2, np.NINF, 6],
    ])
    y = np.array([3, 6, 6, 6, 6])
    classifier = DecisionTreeClassifier()
    pipeline = make_pipeline(FunctionTransformer(replace), classifier)
    pipeline.fit(X, y).predict(X)
    bagging_classifier = BaggingClassifier(pipeline)
    bagging_classifier.fit(X, y)
    y_hat = bagging_classifier.predict(X)
    assert y.shape == y_hat.shape
    bagging_classifier.predict_log_proba(X)
    bagging_classifier.predict_proba(X)

    # Verify that exceptions can be raised by wrapper classifier
    classifier = DecisionTreeClassifier()
    pipeline = make_pipeline(classifier)
    assert_raises(ValueError, pipeline.fit, X, y)
    bagging_classifier = BaggingClassifier(pipeline)
    assert_raises(ValueError, bagging_classifier.fit, X, y)
Ejemplo n.º 2
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def test_warm_start_equal_n_estimators():
    # Test that nothing happens when fitting without increasing n_estimators
    X, y = make_hastie_10_2(n_samples=20, random_state=1)
    X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=43)

    clf = BaggingClassifier(n_estimators=5, warm_start=True, random_state=83)
    clf.fit(X_train, y_train)

    y_pred = clf.predict(X_test)
    # modify X to nonsense values, this should not change anything
    X_train += 1.

    assert_warns_message(
        UserWarning,
        "Warm-start fitting without increasing n_estimators does not", clf.fit,
        X_train, y_train)
    assert_array_equal(y_pred, clf.predict(X_test))
Ejemplo n.º 3
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def test_warm_start_equivalence():
    # warm started classifier with 5+5 estimators should be equivalent to
    # one classifier with 10 estimators
    X, y = make_hastie_10_2(n_samples=20, random_state=1)
    X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=43)

    clf_ws = BaggingClassifier(n_estimators=5,
                               warm_start=True,
                               random_state=3141)
    clf_ws.fit(X_train, y_train)
    clf_ws.set_params(n_estimators=10)
    clf_ws.fit(X_train, y_train)
    y1 = clf_ws.predict(X_test)

    clf = BaggingClassifier(n_estimators=10,
                            warm_start=False,
                            random_state=3141)
    clf.fit(X_train, y_train)
    y2 = clf.predict(X_test)

    assert_array_almost_equal(y1, y2)