def _get_element_to_element_vertex_count(element_to_element_matrix):
    """
    Return a tuple of arrays (elements1, elements2, nvertices).

    The element elements1[i] is connected with elements2[i] via
    nvertices[i] vertices.

    """
    coo_matrix = element_to_element_matrix.tocoo()
    elements1 = coo_matrix.row
    elements2 = coo_matrix.col
    nvertices = coo_matrix.data

    return (elements1, elements2, nvertices)