for (size_t i = 0; i < sss->n; i++)
ctables_summary_add (&cell->summaries[i], &sss->summaries[i], sss->var,
case_data (c, sss->var), weight);
for (size_t i = 0; i < sss->n; i++)
ctables_summary_add (&cell->summaries[i], &sss->summaries[i], sss->var,
case_data (c, sss->var), weight);