def METHOD_NAME(mesh):
    """
    A sparse matrix representation of the face angles.
    Returns
    ----------
    sparse : scipy.sparse.coo_matrix
      matrix is float shaped (len(vertices), len(faces))
    """
    matrix = coo_matrix((
        mesh.face_angles.flatten(),
        (mesh.faces_sparse.row, mesh.faces_sparse.col)),
        mesh.faces_sparse.shape)
    return matrix