X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fmath%2Fpercentiles.h;fp=src%2Fmath%2Fpercentiles.h;h=c79a629fe3623de7b531186ec6ef09dec6e9d329;hb=feb269112e14589474c0a75e96cd5a892d9aaeef;hp=86fd641addd46d5e6c3c955e547421a04649cf65;hpb=922dfe227e0a157f895c025b8f8590e2bfc59f23;p=pspp

diff --git a/src/math/percentiles.h b/src/math/percentiles.h
index 86fd641add..c79a629fe3 100644
--- a/src/math/percentiles.h
+++ b/src/math/percentiles.h
@@ -21,6 +21,16 @@
 
 #include "order-stats.h"
 
+/* To calculate a percentile:
+
+   - Create a "struct percentile" with percentile_create().
+   - Feed in the data with order_stats_accumulate() or
+     order_stats_accumulate_idx().  The data must be in sorted order: if
+     necessary, use one of the sorting functions from sort.h to sort them.
+   - Obtain the percentile with percentile_calculate().
+   - Destroy the data structure with statistic_destroy().
+*/
+
 /* The algorithm used to calculate percentiles */
 enum pc_alg {
   PC_NONE=0,
@@ -48,15 +58,7 @@ struct percentile
   struct k k[2];
 };
 
-/* Create the Pth percentile.
-   W is the total sum of weights in the data set
-*/
 struct percentile *percentile_create (double p, double W);
+double percentile_calculate (const struct percentile *, enum pc_alg);
 
-/* Return the value of the percentile */
-double percentile_calculate (const struct percentile *ptl, enum pc_alg alg);
-
-void percentile_dump (const struct percentile *ptl);
-
-
-#endif
+#endif  /* percentiles.h */