+ return names[function];
+}
+
+static bool
+add_summary (struct ctables_axis *axis,
+ enum ctables_summary_function function, double percentile,
+ const char *label, const struct fmt_spec *format,
+ const struct msg_location *loc)
+{
+ if (axis->op == CTAO_VAR)
+ {
+ if (axis->n_summaries >= axis->allocated_summaries)
+ axis->summaries = x2nrealloc (axis->summaries,
+ &axis->allocated_summaries,
+ sizeof *axis->summaries);
+
+ const char *function_name = ctables_summary_function_name (function);
+ const char *var_name = ctables_var_name (&axis->var);
+ switch (ctables_function_availability (function))
+ {
+ case CTFA_MRSETS:
+ if (!axis->var.is_mrset)
+ {
+ msg_at (SE, loc, _("Summary function %s applies only to multiple "
+ "response sets."), function_name);
+ msg_at (SN, axis->loc, _("'%s' is not a multiple response set."),
+ var_name);
+ return false;
+ }
+ break;
+
+ case CTFA_SCALE:
+ if (!axis->scale)
+ {
+ msg_at (SE, loc,
+ _("Summary function %s applies only to scale variables."),
+ function_name);
+ msg_at (SN, axis->loc, _("'%s' is not a scale variable."),
+ var_name);
+ return false;
+ }
+ break;
+
+ case CTFA_ALL:
+ break;
+ }
+
+ struct ctables_summary *dst = &axis->summaries[axis->n_summaries++];
+ *dst = (struct ctables_summary) {
+ .function = function,
+ .percentile = percentile,
+ .label = xstrdup (label),
+ .format = (format ? *format
+ : ctables_summary_default_format (function, &axis->var)),
+ };
+ return true;
+ }
+ else
+ {
+ for (size_t i = 0; i < 2; i++)
+ if (!add_summary (axis->subs[i], function, percentile, label, format,
+ loc))
+ return false;
+ return true;
+ }