test_gradient_boosting.py 文件源码

def test_staged_functions_defensive():
    # test that staged_functions make defensive copies
    rng = np.random.RandomState(0)
    X = rng.uniform(size=(10, 3))
    y = (4 * X[:, 0]).astype(np.int) + 1  # don't predict zeros
    for estimator in [GradientBoostingRegressor(),
                      GradientBoostingClassifier()]:
        estimator.fit(X, y)
        for func in ['predict', 'decision_function', 'predict_proba']:
            staged_func = getattr(estimator, "staged_" + func, None)
            if staged_func is None:
                # regressor has no staged_predict_proba
                continue
            with warnings.catch_warnings(record=True):
                staged_result = list(staged_func(X))
            staged_result[1][:] = 0
            assert_true(np.all(staged_result[0] != 0))