def build_sparse_matrix_target(limit=0):
        targets_vector = DataDAO.get_targets()
        targets_matrix = []
        for ind, item in enumerate(targets_vector):
            if limit != 0 and ind >= limit:
                break
            multiclass_vector = TrainingFactory.get_category_vector(item)
            targets_matrix.append(multiclass_vector)

        sparse = csr_matrix(targets_matrix)
        return sparse
    def build_target_vector_by_category(category, limit=0):
        targets_vector = DataDAO.get_targets()
        targets_cat = []
        for ind, item in enumerate(targets_vector):
            if limit != 0 and ind >= limit:
                break
            if item == category:
                targets_cat.append(1)
            else:
                targets_cat.append(0)

        return targets_cat