math: Avoid unneeded extra allocations for fixed-size data structures.

[pspp] / src / math / tukey-hinges.c

diff --git a/src/math/tukey-hinges.c b/src/math/tukey-hinges.c
index 95a79c1d30026da280cbc6fa2542518c0ff4ad1f..b59b878ba64991c2bea385553e24c8e058ab8c2e 100644 (file)
--- a/src/math/tukey-hinges.c
+++ b/src/math/tukey-hinges.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2008 Free Software Foundation, Inc.
+   Copyright (C) 2008, 2009, 2011 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
@@ -15,13 +15,17 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
 #include <config.h>
-#include "tukey-hinges.h"
-#include <math/order-stats.h>
 
-#include <gl/xalloc.h>
-#include <libpspp/assertion.h>
+#include "math/tukey-hinges.h"
+
 #include <math.h>
 
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "math/order-stats.h"
+
+#include "gl/xalloc.h"
+
 void
 tukey_hinges_calculate (const struct tukey_hinges *th, double hinge[3])
 {
@@ -37,7 +41,7 @@ tukey_hinges_calculate (const struct tukey_hinges *th, double hinge[3])
 
       if (a_star[i] < 1)
        {
-         if (os->k[i].c_p1 >= 1 )
+         if (os->k[i].c_p1 >= 1)
            {
              hinge[i] = (1 - a_star[i]) * os->k[i].y
                + a_star[i] * os->k[i].y_p1;
@@ -59,26 +63,24 @@ tukey_hinges_calculate (const struct tukey_hinges *th, double hinge[3])
 static void
 destroy (struct statistic *s)
 {
-  struct order_stats *os = (struct order_stats *) s;
-
-  free (os->k);
-  free (s);
+  struct tukey_hinges *th = UP_CAST (s, struct tukey_hinges, parent.parent);
+  free (th);
 };
 
-struct statistic *
+struct tukey_hinges *
 tukey_hinges_create (double W, double c_min)
 {
   double d;
-  struct tukey_hinges *th = xzalloc (sizeof (*th));
-  struct order_stats *os = (struct order_stats *) th;
-  struct statistic *stat = (struct statistic *) th;
+  struct tukey_hinges *th = XZALLOC (struct tukey_hinges);
+  struct order_stats *os = &th->parent;
+  struct statistic *stat = &os->parent;
 
   assert (c_min >= 0);
 
   os->n_k = 3;
-  os->k = xcalloc (sizeof (*os->k), 3);
+  os->k = th->k;
 
-  if ( c_min >= 1.0)
+  if (c_min >= 1.0)
     {
       d = floor ((W + 3) / 2.0) / 2.0;
 
@@ -97,5 +99,5 @@ tukey_hinges_create (double W, double c_min)
 
   stat->destroy = destroy;
 
-  return stat;
+  return th;
 }