[blyatman]

I am trying to extract the number of cells in each cell zone (for use in a separate calculation) with the following UDF:

#include “udf.h”
#include “prox.h”

DEFINE_ON_DEMAND(compute)
{
    #if !RP_HOST

    Domain *domain;
    Thread *tc;

    domain = Get_Domain(ROOT_DOMAIN_ID);

    if (I_AM_NODE_ZERO_P)
    {
        int ntc = 0;
        int nc;
        thread_loop_c(tc,domain)
        {
            ntc += 1;
            nc = 0;
            begin_c_loop(c,tc)
            {
                nc += 1;
            }
            end_c_loop(c,tc)
            Message(“Number of cells: %d\n”,nc);
        }
        Message(“Number of cell threads: %d\n”,ntc);
    }

    #endif
}

I tested this on a mesh with a single cell zone containing 39585 cells. Running the above UDF gives me 10372 cells. If I replace the cell loop with “nc = THREAD_N_ELEMENTS(tc)“, I get 10624 cells. Not sure what’s going on here, as either approaches do not give me the correct number.

I am also only doing the loop over node 0 for other reasons which I won't get in to.