Correct and expand comment to barchart_create

diff --git a/src/output/charts/barchart.c b/src/output/charts/barchart.c
index 5d35719a861796cbf1d82e3ab0f5ea9310e22c12..07a39e818f65193b6ddc6ed4816eab19c3a65dd5 100644 (file)
--- a/src/output/charts/barchart.c
+++ b/src/output/charts/barchart.c
@@ -75,7 +75,14 @@ compare_freq_2level_ptr_3way (const void *a_, const void *b_, const void *bc_)
 
 
 /* Creates and returns a chart that will render a barchart with
-   the given TITLE and the N_BARS described in CATS. */
+   the given TITLE and the N_CATS described in CATS. 
+
+   VAR is an array containing the categorical variables, and N_VAR 
+   the number of them. N_VAR must be exactly 1 or 2.
+
+   CATS are the counts of the values of those variables. N_CATS is the
+   number of distinct values.
+*/
 struct chart_item *
 barchart_create (const struct variable **var, int n_vars,
                 const char *ylabel,