test_randomized_l1.py 文件源码

def test_randomized_logistic():
    # Check randomized sparse logistic regression
    iris = load_iris()
    X = iris.data[:, [0, 2]]
    y = iris.target
    X = X[y != 2]
    y = y[y != 2]

    F, _ = f_classif(X, y)

    scaling = 0.3
    clf = RandomizedLogisticRegression(verbose=False, C=1., random_state=42,
                                       scaling=scaling, n_resampling=50,
                                       tol=1e-3)
    X_orig = X.copy()
    feature_scores = clf.fit(X, y).scores_
    assert_array_equal(X, X_orig)   # fit does not modify X
    assert_array_equal(np.argsort(F), np.argsort(feature_scores))

    clf = RandomizedLogisticRegression(verbose=False, C=[1., 0.5],
                                       random_state=42, scaling=scaling,
                                       n_resampling=50, tol=1e-3)
    feature_scores = clf.fit(X, y).scores_
    assert_array_equal(np.argsort(F), np.argsort(feature_scores))