/* return numrows, numcols, remainder rows for ravel operation */
ravelsize(s = refseries(w0), len = length(s), start = 1, olap = 0)
{
        local size;

        if (isscalar(s))
        {
                olap = start;
                start = len;
                len = s;

                s = refseries(w0);
        }

        /* get ravel sizes only */
        size = ravel(s, len, start, olap, 1);

        return(size[1], size[2], size[3]);
}