/* 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
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
-#include "trimmed-mean.h"
-#include <math/order-stats.h>
-#include <gl/xalloc.h>
-#include <libpspp/assertion.h>
+#include "math/trimmed-mean.h"
+
#include <math.h>
-#include <data/val-type.h>
+#include "data/val-type.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "math/order-stats.h"
+
+#include "gl/xalloc.h"
static void
acc (struct statistic *s, const struct ccase *cx UNUSED, double c, double cc, double y)
{
- struct trimmed_mean *tm = (struct trimmed_mean *) s;
- struct order_stats *os = (struct order_stats *) s;
+ struct trimmed_mean *tm = UP_CAST (s, struct trimmed_mean, parent.parent);
+ struct order_stats *os = &tm->parent;
- if ( cc > os->k[0].tc && cc < os->k[1].tc)
- tm->sum += c * y;
+ if (cc > os->k[0].tc && cc <= os->k[1].tc)
+ tm->sum += c * y;
- if ( tm->cyk1p1 == SYSMIS && cc >os->k[0].tc)
- tm->cyk1p1 = c * y;
+ if (tm->cyk1p1 == SYSMIS && cc > os->k[0].tc)
+ tm->cyk1p1 = c * y;
}
static void
destroy (struct statistic *s)
{
- struct order_stats *os = (struct order_stats *) s;
- free (os->k);
- free (s);
+ struct trimmed_mean *tm = UP_CAST (s, struct trimmed_mean, parent.parent);
+ free (tm);
}
-struct statistic *
+struct trimmed_mean *
trimmed_mean_create (double W, double tail)
{
- struct trimmed_mean *tm = xzalloc (sizeof (*tm));
- struct order_stats *os = (struct order_stats *) tm;
- struct statistic *stat = (struct statistic *) tm;
-
- os->n_k = 2;
- os->k = xcalloc (sizeof (*os->k), 2);
-
assert (tail >= 0);
assert (tail <= 1);
- os->k[0].tc = tail * W;
- os->k[1].tc = W * (1 - tail);
-
- stat->accumulate = acc;
- stat->destroy = destroy;
-
- tm->cyk1p1 = SYSMIS;
- tm->w = W;
- tm->tail = tail;
-
- return stat;
+ struct trimmed_mean *tm = xmalloc (sizeof *tm);
+ *tm = (struct trimmed_mean) {
+ .parent = {
+ .parent = {
+ .destroy = destroy,
+ },
+ .accumulate = acc,
+ .k = tm->k,
+ .n_k = 2,
+ },
+ .k[0] = { .tc = tail * W },
+ .k[1] = { .tc = W * (1 - tail) },
+ .cyk1p1 = SYSMIS,
+ .w = W,
+ .tail = tail,
+ };
+ return tm;
}
-
double
trimmed_mean_calculate (const struct trimmed_mean *tm)
{
const struct order_stats *os = (const struct order_stats *) tm;
- assert (os->cc == tm->w);
-
return
(
- (os->k[0].cc_p1 - os->k[0].tc) * os->k[0].y_p1
- -
- (os->k[1].cc - os->k[1].tc) * os->k[1].y_p1
+ (os->k[0].cc - os->k[0].tc) * os->k[0].y_p1
+ +
+ (tm->w - os->k[1].cc - os->k[0].tc) * os->k[1].y_p1
+
- tm->sum
- -
- tm->cyk1p1
- )
- /
- ( (1.0 - 2 * tm->tail) * tm->w);
+ tm->sum
+)
+ / ((1.0 - tm->tail * 2) * tm->w);
}