math: Improve comments.

[pspp] / src / math / percentiles.c

diff --git a/src/math/percentiles.c b/src/math/percentiles.c
index 1b4ff136328ecdbe0ba9fb2cd1bff521519d5803..79514eb2504f95d9fd3bfad37c3854aa8fe8c510 100644 (file)
--- a/src/math/percentiles.c
+++ b/src/math/percentiles.c
@@ -27,6 +27,7 @@
 
 #include "gl/xalloc.h"
 
+/* Return the value of the percentile. */
 double
 percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
 {
@@ -143,6 +144,9 @@ destroy (struct statistic *stat)
 }
 
 
+/* Create the Pth percentile.
+   W is the total sum of weights in the data set.
+*/
 struct percentile *
 percentile_create (double p, double W)
 {