test_split.py 文件源码

def test_shuffle_kfold():
    # Check the indices are shuffled properly
    kf = KFold(3)
    kf2 = KFold(3, shuffle=True, random_state=0)
    kf3 = KFold(3, shuffle=True, random_state=1)

    X = np.ones(300)

    all_folds = np.zeros(300)
    for (tr1, te1), (tr2, te2), (tr3, te3) in zip(
            kf.split(X), kf2.split(X), kf3.split(X)):
        for tr_a, tr_b in combinations((tr1, tr2, tr3), 2):
            # Assert that there is no complete overlap
            assert_not_equal(len(np.intersect1d(tr_a, tr_b)), len(tr1))

        # Set all test indices in successive iterations of kf2 to 1
        all_folds[te2] = 1

    # Check that all indices are returned in the different test folds
    assert_equal(sum(all_folds), 300)