def export_UVfactors(filepath, uv_matrices, layer_names):
    """Export UV-matrices, including the length of a real edge an its
    UV-distance

    :param str filename: export filename
    :param numpy.Array uv_matrices:
    :param list layer_names:

    .. note::
        * uv_matrices: list of uv-matrices
        * layer_names: list of layer-names, the order corresponds to the
          list-order in uv_matrices
    """
    with zipfile.ZipFile(filepath, 'w', zipfile.ZIP_DEFLATED) as file:
        for i, matrix in enumerate(uv_matrices):
            csv_write_matrix(file, layer_names[i], [matrix])