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authorscuri <scuri>2008-10-17 06:10:15 +0000
committerscuri <scuri>2008-10-17 06:10:15 +0000
commit5a422aba704c375a307a902bafe658342e209906 (patch)
tree5005011e086bb863d8fb587ad3319bbec59b2447 /src/fftw3/rdft/dht-r2hc.c
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/fftw3/rdft/dht-r2hc.c')
-rw-r--r--src/fftw3/rdft/dht-r2hc.c148
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diff --git a/src/fftw3/rdft/dht-r2hc.c b/src/fftw3/rdft/dht-r2hc.c
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+++ b/src/fftw3/rdft/dht-r2hc.c
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+/*
+ * Copyright (c) 2003 Matteo Frigo
+ * Copyright (c) 2003 Massachusetts Institute of Technology
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/* $Id: dht-r2hc.c,v 1.1 2008/10/17 06:11:29 scuri Exp $ */
+
+/* Solve a DHT problem (Discrete Hartley Transform) via post-processing
+ of an R2HC problem. */
+
+#include "rdft.h"
+
+typedef struct {
+ solver super;
+} S;
+
+typedef struct {
+ plan_rdft super;
+ plan *cld;
+ int os;
+ int n;
+} P;
+
+static void apply(const plan *ego_, R *I, R *O)
+{
+ const P *ego = (const P *) ego_;
+ int os = ego->os;
+ int i, n = ego->n;
+
+ {
+ plan_rdft *cld = (plan_rdft *) ego->cld;
+ cld->apply((plan *) cld, I, O);
+ }
+
+ for (i = 1; i < n - i; ++i) {
+ E a, b;
+ a = O[os * i];
+ b = O[os * (n - i)];
+#if FFT_SIGN == -1
+ O[os * i] = a - b;
+ O[os * (n - i)] = a + b;
+#else
+ O[os * i] = a + b;
+ O[os * (n - i)] = a - b;
+#endif
+ }
+}
+
+static void awake(plan *ego_, int flg)
+{
+ P *ego = (P *) ego_;
+ AWAKE(ego->cld, flg);
+}
+
+static void destroy(plan *ego_)
+{
+ P *ego = (P *) ego_;
+ X(plan_destroy_internal)(ego->cld);
+}
+
+static void print(const plan *ego_, printer *p)
+{
+ const P *ego = (const P *) ego_;
+ p->print(p, "(dht-r2hc-%d%(%p%))", ego->n, ego->cld);
+}
+
+static int applicable0(const problem *p_, const planner *plnr)
+{
+ if (RDFTP(p_)) {
+ const problem_rdft *p = (const problem_rdft *) p_;
+ return (1
+ && !NO_DHT_R2HCP(plnr)
+ && p->sz->rnk == 1
+ && p->vecsz->rnk == 0
+ && p->kind[0] == DHT
+ );
+ }
+ return 0;
+}
+
+static int applicable(const solver *ego, const problem *p, const planner *plnr)
+{
+ UNUSED(ego);
+ return (!NO_UGLYP(plnr) && applicable0(p, plnr));
+}
+
+static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
+{
+ P *pln;
+ const problem_rdft *p;
+ plan *cld;
+
+ static const plan_adt padt = {
+ X(rdft_solve), awake, print, destroy
+ };
+
+ if (!applicable(ego_, p_, plnr))
+ return (plan *)0;
+
+ p = (const problem_rdft *) p_;
+
+ /* stop infinite loops with rdft-dht.c */
+ plnr->problem_flags |= NO_DHT_R2HC;
+
+ cld = X(mkplan_d)(plnr,
+ X(mkproblem_rdft_1)(p->sz, p->vecsz, p->I, p->O, R2HC));
+ if (!cld) return (plan *)0;
+
+ pln = MKPLAN_RDFT(P, &padt, apply);
+
+ pln->n = p->sz->dims[0].n;
+ pln->os = p->sz->dims[0].os;
+ pln->cld = cld;
+
+ pln->super.super.ops = cld->ops;
+ pln->super.super.ops.other += 4 * ((pln->n - 1)/2);
+ pln->super.super.ops.add += 2 * ((pln->n - 1)/2);
+
+ return &(pln->super.super);
+}
+
+/* constructor */
+static solver *mksolver(void)
+{
+ static const solver_adt sadt = { mkplan };
+ S *slv = MKSOLVER(S, &sadt);
+ return &(slv->super);
+}
+
+void X(dht_r2hc_register)(planner *p)
+{
+ REGISTER_SOLVER(p, mksolver());
+}