test_classification.py 文件源码

def test_multilabel_hamming_loss():
    # Dense label indicator matrix format
    y1 = np.array([[0, 1, 1], [1, 0, 1]])
    y2 = np.array([[0, 0, 1], [1, 0, 1]])
    w = np.array([1, 3])

    assert_equal(hamming_loss(y1, y2), 1 / 6)
    assert_equal(hamming_loss(y1, y1), 0)
    assert_equal(hamming_loss(y2, y2), 0)
    assert_equal(hamming_loss(y2, 1 - y2), 1)
    assert_equal(hamming_loss(y1, 1 - y1), 1)
    assert_equal(hamming_loss(y1, np.zeros(y1.shape)), 4 / 6)
    assert_equal(hamming_loss(y2, np.zeros(y1.shape)), 0.5)
    assert_equal(hamming_loss(y1, y2, sample_weight=w), 1. / 12)
    assert_equal(hamming_loss(y1, 1-y2, sample_weight=w), 11. / 12)
    assert_equal(hamming_loss(y1, np.zeros_like(y1), sample_weight=w), 2. / 3)
    # sp_hamming only works with 1-D arrays
    assert_equal(hamming_loss(y1[0], y2[0]), sp_hamming(y1[0], y2[0]))