I developed a function (shown below) to check if a sparse matrix is symmetric and would like to know if the community is interested to include in scipy.sparse.

Regards,

Saullo

def is_symmetric(m):

    """Check if a sparse matrix is symmetric

    Parameters

    ----------

    m : array or sparse matrix

        A square matrix.

    Returns

    -------

    check : bool

        The check result.

    """

    if m.shape[0] != m.shape[1]:

        raise ValueError('m must be a square matrix')

    if not isinstance(m, coo_matrix):

        m = coo_matrix(m)

    r, c, v = m.row, m.col, m.data

    tril_no_diag = r > c

    triu_no_diag = c > r

    if triu_no_diag.sum() != tril_no_diag.sum():

        return False

    rl = r[tril_no_diag]

    cl = c[tril_no_diag]

    vl = v[tril_no_diag]

    ru = r[triu_no_diag]

    cu = c[triu_no_diag]

    vu = v[triu_no_diag]

    sortl = np.lexsort((cl, rl))

    sortu = np.lexsort((ru, cu))

    vl = vl[sortl]

    vu = vu[sortu]

    check = np.allclose(vl, vu)

    return check

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