X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fmath%2Fhistogram.c;h=3c88c3858f61c6b1c2230843a7b9151a47902956;hb=b1b30577f94f321a2e7dca1e5cb1e12ef38c6310;hp=67079398d169ec58737c6f3b94a7d243b9fc8516;hpb=9a331fe64eb814ae5c1322e21717a04fb254bf65;p=pspp

diff --git a/src/math/histogram.c b/src/math/histogram.c
index 67079398d1..3c88c3858f 100644
--- a/src/math/histogram.c
+++ b/src/math/histogram.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2004, 2008 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2008, 2009 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -19,6 +19,7 @@
 
 #include <gl/xalloc.h>
 #include <libpspp/assertion.h>
+#include <libpspp/cast.h>
 
 #include <gsl/gsl_histogram.h>
 #include "chart-geometry.h"
@@ -28,7 +29,8 @@
 void
 histogram_add (struct histogram *h, double y, double c)
 {
-  ((struct statistic *)h)->accumulate ((struct statistic *) h, NULL, c, 0, y);
+  struct statistic *stat = &h->parent;
+  stat->accumulate (stat, NULL, c, 0, y);
 }
 
 
@@ -36,7 +38,7 @@ histogram_add (struct histogram *h, double y, double c)
 static void
 acc (struct statistic *s, const struct ccase *cx UNUSED, double c, double cc UNUSED, double y)
 {
-  struct histogram *hist = (struct histogram *) s;
+  struct histogram *hist = UP_CAST (s, struct histogram, parent);
 
   gsl_histogram_accumulate (hist->gsl_hist, y, c);
 }
@@ -45,17 +47,17 @@ acc (struct statistic *s, const struct ccase *cx UNUSED, double c, double cc UNU
 static void
 destroy (struct statistic *s)
 {
-  struct histogram *h = (struct histogram *) s;
+  struct histogram *h = UP_CAST (s, struct histogram, parent);
   gsl_histogram_free (h->gsl_hist);
   free (s);
 }
 
 
-struct statistic *
+struct histogram *
 histogram_create (int bins, double min, double max)
 {
   struct histogram *h = xmalloc (sizeof *h);
-  struct statistic *stat = (struct statistic *) h;
+  struct statistic *stat = &h->parent;
   double upper_limit, lower_limit;
 
   double bin_width = chart_rounded_tick ((max - min) / (double) bins);
@@ -78,6 +80,6 @@ histogram_create (int bins, double min, double max)
   stat->accumulate = acc;
   stat->destroy = destroy;
 
-  return stat;
+  return h;
 }