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

[pspp] / src / math / percentiles.c

diff --git a/src/math/percentiles.c b/src/math/percentiles.c
index 53d704d623036981d99ae49d49677498542e010a..1b4ff136328ecdbe0ba9fb2cd1bff521519d5803 100644 (file)
--- a/src/math/percentiles.c
+++ b/src/math/percentiles.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
@@ -15,59 +15,45 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
 #include <config.h>
-#include "percentiles.h"
-#include <math/order-stats.h>
 
+#include "math/percentiles.h"
 
-#include "gettext.h"
-#define _(msgid) gettext (msgid)
-#define N_(msgid) msgid
-
-#include <libpspp/assertion.h>
-#include <data/val-type.h>
-#include <gl/xalloc.h>
-#include <data/variable.h>
-#include <data/casereader.h>
-
-
-const char *const ptile_alg_desc[] = {
-  "",
-  N_("HAverage"),
-  N_("Weighted Average"),
-  N_("Rounded"),
-  N_("Empirical"),
-  N_("Empirical with averaging")
-};
-
+#include "data/casereader.h"
+#include "data/val-type.h"
+#include "data/variable.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "math/order-stats.h"
 
+#include "gl/xalloc.h"
 
 double
 percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
 {
-  struct percentile *mutable = (struct percentile *) ptl;
+  struct percentile *mutable = CONST_CAST (struct percentile *, ptl);
   const struct order_stats *os = &ptl->parent;
 
-  if ( ptl->g1 == SYSMIS)
+  if (ptl->g1 == SYSMIS)
     mutable->g1 = (os->k[0].tc - os->k[0].cc) / os->k[0].c_p1;
 
-  if ( ptl->g1_star == SYSMIS)
+  if (ptl->g1_star == SYSMIS)
     mutable->g1_star = os->k[0].tc - os->k[0].cc;
 
-  if ( ptl->g2 == SYSMIS)
+  if (ptl->g2 == SYSMIS)
     {
-      if ( os->k[1].c == 0 )
+      if (os->k[1].c == 0)
        mutable->g2 = os->k[1].tc / os->k[1].c_p1;
-      else if ( os->k[1].c_p1 == 0 )
+      else if (os->k[1].c_p1 == 0)
        mutable->g2 = 0;
       else
        mutable->g2 = (os->k[1].tc - os->k[1].cc) / os->k[1].c_p1;
     }
 
-  if ( ptl->g2_star == SYSMIS)
+  if (ptl->g2_star == SYSMIS)
     {
-      if ( os->k[1].c == 0 )
+      if (os->k[1].c == 0)
        mutable->g2_star = os->k[1].tc;
-      else if ( os->k[1].c_p1 == 0 )
+      else if (os->k[1].c_p1 == 0)
        mutable->g2_star = 0;
       else
        mutable->g2_star = os->k[1].tc - os->k[1].cc;
@@ -76,11 +62,11 @@ percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
   switch (alg)
     {
     case PC_WAVERAGE:
-      if ( ptl->g1_star >= 1.0)
+      if (ptl->g1_star >= 1.0)
        return os->k[0].y_p1;
       else
        {
-         double a = ( os->k[0].y == SYSMIS ) ? 0 : os->k[0].y;
+         double a = (os->k[0].y == SYSMIS) ? 0 : os->k[0].y;
 
          if (os->k[0].c_p1 >= 1.0)
            return (1 - ptl->g1_star) * a + ptl->g1_star * os->k[0].y_p1;
@@ -91,7 +77,7 @@ percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
 
     case PC_ROUND:
       {
-       double a = ( os->k[0].y == SYSMIS ) ? 0 : os->k[0].y;
+       double a = (os->k[0].y == SYSMIS) ? 0 : os->k[0].y;
 
        if (os->k[0].c_p1 >= 1.0)
          return (ptl->g1_star < 0.5) ? a : os->k[0].y_p1;
@@ -101,24 +87,24 @@ percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
       break;
 
     case PC_EMPIRICAL:
-      if ( ptl->g1_star == 0 )
+      if (ptl->g1_star == 0)
        return os->k[0].y;
       else
        return os->k[0].y_p1;
       break;
 
     case PC_HAVERAGE:
-      if ( ptl->g2_star >= 1.0)
+      if (ptl->g2_star >= 1.0)
        {
          return os->k[1].y_p1;
        }
       else
        {
-         double a = ( os->k[1].y == SYSMIS ) ? 0 : os->k[1].y;
+         double a = (os->k[1].y == SYSMIS) ? 0 : os->k[1].y;
 
-         if ( os->k[1].c_p1 >= 1.0)
+         if (os->k[1].c_p1 >= 1.0)
            {
-             if ( ptl->g2_star == 0)
+             if (ptl->g2_star == 0)
                return os->k[1].y;
 
              return (1 - ptl->g2_star) * a + ptl->g2_star * os->k[1].y_p1;
@@ -132,7 +118,7 @@ percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
       break;
 
     case PC_AEMPIRICAL:
-      if ( ptl->g1_star == 0 )
+      if (ptl->g1_star == 0)
        return (os->k[0].y + os->k[0].y_p1)/ 2.0;
       else
        return os->k[0].y_p1;
@@ -152,26 +138,26 @@ percentile_calculate (const struct percentile *ptl, enum pc_alg alg)
 static void
 destroy (struct statistic *stat)
 {
-  struct order_stats *os = (struct order_stats *) stat;
-  free (os->k);
-  free (os);
+  struct percentile *ptl = UP_CAST (stat, struct percentile, parent.parent);
+  free (ptl);
 }
 
 
-struct order_stats *
+struct percentile *
 percentile_create (double p, double W)
 {
-  struct percentile *ptl = xzalloc (sizeof (*ptl));
-  struct order_stats *os = (struct order_stats *) ptl;
-  struct statistic *stat = (struct statistic *) ptl;
+  struct percentile *ptl = XZALLOC (struct percentile);
+  struct order_stats *os = &ptl->parent;
+  struct statistic *stat = &os->parent;
 
   assert (p >= 0);
   assert (p <= 1.0);
 
   ptl->ptile = p;
+  ptl->w = W;
 
   os->n_k = 2;
-  os->k = xcalloc (sizeof (*os->k), 2);
+  os->k = ptl->k;
   os->k[0].tc = W * p;
   os->k[1].tc = (W + 1.0) * p;
 
@@ -183,18 +169,6 @@ percentile_create (double p, double W)
 
   stat->destroy = destroy;
 
-  return os;
+  return ptl;
 }
 
-#if 0
-void
-percentile_dump (const struct percentile *ptl)
-{
-  printf ("Percentile %g:\n\tk1: ", ptl->ptile);
-
-  dump_os_k1 ((const struct os *)ptl);
-  printf ("\tk2: ");
-  dump_os_k2 ((const struct os *)ptl);
-  printf ("\n");
-}
-#endif