test_ranking_svm.py 文件源码

def test_rank_archimedean_spiral():
    def archimedean_spiral(n_steps=100, max_radius=1.0, turns=4.0):
        r = np.linspace(0.0, max_radius, n_steps)
        angle = r * 2.0 * np.pi * turns / max_radius
        x = r * np.cos(angle)
        y = r * np.sin(angle)
        return np.hstack((x[:, np.newaxis], y[:, np.newaxis])), r

    X_train, r_train = archimedean_spiral(n_steps=100)
    X_test, r_test = archimedean_spiral(n_steps=1000, max_radius=1.1)

    rsvm = RankingSVM(random_state=0)
    rsvm.fit(X_train)

    y_train = rsvm.predict(X_train)
    y_test = rsvm.predict(X_test)
    assert_true(np.all(y_train[1:] < y_train[:-1]))
    assert_greater(np.count_nonzero(y_test[1:] < y_test[:-1]), 970)