Function check_class_proba

modAL/utils/validation.py:30–55

Checks the class probabilities and reshapes it if not all labels are present in the classifier. Args: proba: The class probabilities of a classifier. known_labels: The class labels known by the classifier. all_labels: All class labels. Returns: Class pr

(proba: np.ndarray, known_labels: Sequence, all_labels: Sequence)

def check_class_proba(proba: np.ndarray, known_labels: Sequence, all_labels: Sequence) -> np.ndarray:
    """
    Checks the class probabilities and reshapes it if not all labels are present in the classifier.

    Args:
        proba: The class probabilities of a classifier.
        known_labels: The class labels known by the classifier.
        all_labels: All class labels.

    Returns:
        Class probabilities augmented such that the probability of all classes is present. If the classifier is unaware
        of a particular class, all probabilities are zero.
    """
    # TODO: rewrite this function using numpy.insert

    label_idx_map = -np.ones(len(all_labels), dtype='int')

    for known_label_idx, known_label in enumerate(known_labels):
        # finds the position of label in all_labels
        for label_idx, label in enumerate(all_labels):
            if np.array_equal(label, known_label):
                label_idx_map[label_idx] = known_label_idx
                break

    aug_proba = np.hstack((proba, np.zeros(shape=(proba.shape[0], 1))))
    return aug_proba[:, label_idx_map]