test_weight_boosting.py 文件源码

def test_base_estimator():
    # Test different base estimators.
    from sklearn.ensemble import RandomForestClassifier
    from sklearn.svm import SVC

    # XXX doesn't work with y_class because RF doesn't support classes_
    # Shouldn't AdaBoost run a LabelBinarizer?
    clf = AdaBoostClassifier(RandomForestClassifier())
    clf.fit(X, y_regr)

    clf = AdaBoostClassifier(SVC(), algorithm="SAMME")
    clf.fit(X, y_class)

    from sklearn.ensemble import RandomForestRegressor
    from sklearn.svm import SVR

    clf = AdaBoostRegressor(RandomForestRegressor(), random_state=0)
    clf.fit(X, y_regr)

    clf = AdaBoostRegressor(SVR(), random_state=0)
    clf.fit(X, y_regr)

    # Check that an empty discrete ensemble fails in fit, not predict.
    X_fail = [[1, 1], [1, 1], [1, 1], [1, 1]]
    y_fail = ["foo", "bar", 1, 2]
    clf = AdaBoostClassifier(SVC(), algorithm="SAMME")
    assert_raises_regexp(ValueError, "worse than random",
                         clf.fit, X_fail, y_fail)