Ejemplo n.º 1
0
def test_label_binarizer_errors():
    # Check that invalid arguments yield ValueError
    one_class = np.array([0, 0, 0, 0])
    lb = LabelBinarizer().fit(one_class)

    multi_label = [(2, 3), (0,), (0, 2)]
    with pytest.raises(ValueError):
        lb.transform(multi_label)

    lb = LabelBinarizer()
    with pytest.raises(ValueError):
        lb.transform([])
    with pytest.raises(ValueError):
        lb.inverse_transform([])

    with pytest.raises(ValueError):
        LabelBinarizer(neg_label=2, pos_label=1)
    with pytest.raises(ValueError):
        LabelBinarizer(neg_label=2, pos_label=2)

    with pytest.raises(ValueError):
        LabelBinarizer(neg_label=1, pos_label=2, sparse_output=True)

    # Fail on y_type
    with pytest.raises(ValueError):
        _inverse_binarize_thresholding(
            y=csr_matrix([[1, 2], [2, 1]]),
            output_type="foo",
            classes=[1, 2],
            threshold=0,
        )

    # Sequence of seq type should raise ValueError
    y_seq_of_seqs = [[], [1, 2], [3], [0, 1, 3], [2]]
    with pytest.raises(ValueError):
        LabelBinarizer().fit_transform(y_seq_of_seqs)

    # Fail on the number of classes
    with pytest.raises(ValueError):
        _inverse_binarize_thresholding(
            y=csr_matrix([[1, 2], [2, 1]]),
            output_type="foo",
            classes=[1, 2, 3],
            threshold=0,
        )

    # Fail on the dimension of 'binary'
    with pytest.raises(ValueError):
        _inverse_binarize_thresholding(
            y=np.array([[1, 2, 3], [2, 1, 3]]),
            output_type="binary",
            classes=[1, 2, 3],
            threshold=0,
        )

    # Fail on multioutput data
    with pytest.raises(ValueError):
        LabelBinarizer().fit(np.array([[1, 3], [2, 1]]))
    with pytest.raises(ValueError):
        label_binarize(np.array([[1, 3], [2, 1]]), classes=[1, 2, 3])
Ejemplo n.º 2
0
def test_label_binarizer_unseen_labels():
    lb = LabelBinarizer()

    expected = np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]])
    got = lb.fit_transform(['b', 'd', 'e'])
    assert_array_equal(expected, got)

    expected = np.array([[0, 0, 0], [1, 0, 0], [0, 0, 0], [0, 1, 0], [0, 0, 1],
                         [0, 0, 0]])
    got = lb.transform(['a', 'b', 'c', 'd', 'e', 'f'])
    assert_array_equal(expected, got)
Ejemplo n.º 3
0
def test_label_binarizer_unseen_labels():
    lb = LabelBinarizer()

    expected = np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]])
    got = lb.fit_transform(["b", "d", "e"])
    assert_array_equal(expected, got)

    expected = np.array([[0, 0, 0], [1, 0, 0], [0, 0, 0], [0, 1, 0], [0, 0, 1],
                         [0, 0, 0]])
    got = lb.transform(["a", "b", "c", "d", "e", "f"])
    assert_array_equal(expected, got)
Ejemplo n.º 4
0
def test_label_binarizer_errors():
    # Check that invalid arguments yield ValueError
    one_class = np.array([0, 0, 0, 0])
    lb = LabelBinarizer().fit(one_class)

    multi_label = [(2, 3), (0, ), (0, 2)]
    err_msg = "You appear to be using a legacy multi-label data representation."
    with pytest.raises(ValueError, match=err_msg):
        lb.transform(multi_label)

    lb = LabelBinarizer()
    err_msg = "This LabelBinarizer instance is not fitted yet"
    with pytest.raises(ValueError, match=err_msg):
        lb.transform([])
    with pytest.raises(ValueError, match=err_msg):
        lb.inverse_transform([])

    input_labels = [0, 1, 0, 1]
    err_msg = "neg_label=2 must be strictly less than pos_label=1."
    lb = LabelBinarizer(neg_label=2, pos_label=1)
    with pytest.raises(ValueError, match=err_msg):
        lb.fit(input_labels)
    err_msg = "neg_label=2 must be strictly less than pos_label=2."
    lb = LabelBinarizer(neg_label=2, pos_label=2)
    with pytest.raises(ValueError, match=err_msg):
        lb.fit(input_labels)
    err_msg = (
        "Sparse binarization is only supported with non zero pos_label and zero "
        "neg_label, got pos_label=2 and neg_label=1")
    lb = LabelBinarizer(neg_label=1, pos_label=2, sparse_output=True)
    with pytest.raises(ValueError, match=err_msg):
        lb.fit(input_labels)

    # Fail on y_type
    err_msg = "foo format is not supported"
    with pytest.raises(ValueError, match=err_msg):
        _inverse_binarize_thresholding(
            y=csr_matrix([[1, 2], [2, 1]]),
            output_type="foo",
            classes=[1, 2],
            threshold=0,
        )

    # Sequence of seq type should raise ValueError
    y_seq_of_seqs = [[], [1, 2], [3], [0, 1, 3], [2]]
    err_msg = "You appear to be using a legacy multi-label data representation"
    with pytest.raises(ValueError, match=err_msg):
        LabelBinarizer().fit_transform(y_seq_of_seqs)

    # Fail on the number of classes
    err_msg = "The number of class is not equal to the number of dimension of y."
    with pytest.raises(ValueError, match=err_msg):
        _inverse_binarize_thresholding(
            y=csr_matrix([[1, 2], [2, 1]]),
            output_type="foo",
            classes=[1, 2, 3],
            threshold=0,
        )

    # Fail on the dimension of 'binary'
    err_msg = "output_type='binary', but y.shape"
    with pytest.raises(ValueError, match=err_msg):
        _inverse_binarize_thresholding(
            y=np.array([[1, 2, 3], [2, 1, 3]]),
            output_type="binary",
            classes=[1, 2, 3],
            threshold=0,
        )

    # Fail on multioutput data
    err_msg = "Multioutput target data is not supported with label binarization"
    with pytest.raises(ValueError, match=err_msg):
        LabelBinarizer().fit(np.array([[1, 3], [2, 1]]))
    with pytest.raises(ValueError, match=err_msg):
        label_binarize(np.array([[1, 3], [2, 1]]), classes=[1, 2, 3])
Ejemplo n.º 5
0
def class_report(y_true, y_pred, y_score=None, average='micro'):
    if y_true.shape != y_pred.shape:
        print("Error! y_true %s is not the same shape as y_pred %s" %
              (y_true.shape, y_pred.shape))
        return

    lb = LabelBinarizer()

    if len(y_true.shape) == 1:
        lb.fit(y_true)

    #Value counts of predictions
    labels, cnt = np.unique(y_pred, return_counts=True)
    n_classes = len(labels)
    pred_cnt = pd.Series(cnt, index=labels)

    metrics_summary = precision_recall_fscore_support(y_true=y_true,
                                                      y_pred=y_pred,
                                                      labels=labels)

    avg = list(
        precision_recall_fscore_support(y_true=y_true,
                                        y_pred=y_pred,
                                        average='weighted'))

    metrics_sum_index = ['precision', 'recall', 'f1-score', 'support']
    class_report_df = pd.DataFrame(list(metrics_summary),
                                   index=metrics_sum_index,
                                   columns=labels)

    support = class_report_df.loc['support']
    total = support.sum()
    class_report_df['avg / total'] = avg[:-1] + [total]

    class_report_df = class_report_df.T
    class_report_df['pred'] = pred_cnt
    class_report_df['pred'].iloc[-1] = total

    if not (y_score is None):
        fpr = dict()
        tpr = dict()
        roc_auc = dict()
        for label_it, label in enumerate(labels):
            fpr[label], tpr[label], _ = roc_curve(
                (y_true == label).astype(int), y_score[:, label_it])

            roc_auc[label] = auc(fpr[label], tpr[label])

        if average == 'micro':
            if n_classes <= 2:
                fpr["avg / total"], tpr["avg / total"], _ = roc_curve(
                    lb.transform(y_true).ravel(), y_score[:, 1].ravel())
            else:
                fpr["avg / total"], tpr["avg / total"], _ = roc_curve(
                    lb.transform(y_true).ravel(), y_score.ravel())

            roc_auc["avg / total"] = auc(fpr["avg / total"],
                                         tpr["avg / total"])

        elif average == 'macro':
            # First aggregate all false positive rates
            all_fpr = np.unique(np.concatenate([fpr[i] for i in labels]))

            # Then interpolate all ROC curves at this points
            mean_tpr = np.zeros_like(all_fpr)
            for i in labels:
                mean_tpr += interp(all_fpr, fpr[i], tpr[i])

            # Finally average it and compute AUC
            mean_tpr /= n_classes

            fpr["macro"] = all_fpr
            tpr["macro"] = mean_tpr

            roc_auc["avg / total"] = auc(fpr["macro"], tpr["macro"])

        class_report_df['AUC'] = pd.Series(roc_auc)

    return class_report_df