int gi = CCTK_GroupIndexFromVarI(RDWR.var_id);

    int gi = CCTK_GroupIndexFromVarI(RDWR.varindex);

    int vi = RDWR.var_id - CCTK_FirstVarIndexI(gi);

    int vi = RDWR.varindex - CCTK_FirstVarIndexI(gi);

    int tl = RDWR.time_level;

    int tl = RDWR.timelevel;