test_mlp.py 文件源码

def test_learning_rate_warmstart():
    # Tests that warm_start reuses past solution."""
    X = [[3, 2], [1, 6], [5, 6], [-2, -4]]
    y = [1, 1, 1, 0]
    for learning_rate in ["invscaling", "constant"]:
        mlp = MLPClassifier(algorithm='sgd', hidden_layer_sizes=4,
                            learning_rate=learning_rate, max_iter=1,
                            power_t=0.25, warm_start=True)
        mlp.fit(X, y)
        prev_eta = mlp._optimizer.learning_rate
        mlp.fit(X, y)
        post_eta = mlp._optimizer.learning_rate

        if learning_rate == 'constant':
            assert_equal(prev_eta, post_eta)
        elif learning_rate == 'invscaling':
            assert_equal(mlp.learning_rate_init / pow(8 + 1, mlp.power_t),
                         post_eta)