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