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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/dft-r2hc.c
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/fftw3/rdft/dft-r2hc.c')
-rw-r--r--src/fftw3/rdft/dft-r2hc.c187
1 files changed, 187 insertions, 0 deletions
diff --git a/src/fftw3/rdft/dft-r2hc.c b/src/fftw3/rdft/dft-r2hc.c
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+++ b/src/fftw3/rdft/dft-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: dft-r2hc.c,v 1.1 2008/10/17 06:11:29 scuri Exp $ */
+
+/* Compute the complex DFT by combining R2HC RDFTs on the real
+ and imaginary parts. This could be useful for people just wanting
+ to link to the real codelets and not the complex ones. It could
+ also even be faster than the complex algorithms for split (as opposed
+ to interleaved) real/imag complex data. */
+
+#include "rdft.h"
+#include "dft.h"
+
+typedef struct {
+ solver super;
+} S;
+
+typedef struct {
+ plan_dft super;
+ plan *cld;
+ int os;
+ int n;
+} P;
+
+static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io)
+{
+ const P *ego = (const P *) ego_;
+ int os;
+ int i, n;
+
+ UNUSED(ii);
+
+ { /* transform vector of real & imag parts: */
+ plan_rdft *cld = (plan_rdft *) ego->cld;
+ cld->apply((plan *) cld, ri, ro);
+ }
+
+ os = ego->os;
+ n = ego->n;
+ for (i = 1; i < (n + 1)/2; ++i) {
+ R rop, iop, iom, rom;
+ rop = ro[os * i];
+ iop = io[os * i];
+ rom = ro[os * (n - i)];
+ iom = io[os * (n - i)];
+ ro[os * i] = rop - iom;
+ io[os * i] = iop + rom;
+ ro[os * (n - i)] = rop + iom;
+ io[os * (n - i)] = iop - rom;
+ }
+}
+
+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, "(dft-r2hc-%d%(%p%))", ego->n, ego->cld);
+}
+
+#define ALLOW_RANK0 0 /* disable for now, subject to testing */
+
+static int applicable0(const problem *p_)
+{
+ if (DFTP(p_)) {
+ const problem_dft *p = (const problem_dft *) p_;
+ return ((p->sz->rnk == 1 && p->vecsz->rnk == 0)
+#if ALLOW_RANK0
+ || p->sz->rnk == 0
+#endif
+ );
+ }
+
+ return 0;
+}
+
+static int split(R *r, R *i, int n, int s)
+{
+ return ((r > i ? r - i : i - r) >= ((int)n) * (s > 0 ? s : -s));
+}
+
+static int applicable(const problem *p_, const planner *plnr)
+{
+ if (!applicable0(p_)) return 0;
+
+ {
+ const problem_dft *p = (const problem_dft *) p_;
+ if (NO_UGLYP(plnr) && DFT_R2HC_ICKYP(plnr)) return 0;
+
+ if (p->sz->rnk == 1 &&
+ split(p->ri, p->ii, p->sz->dims[0].n, p->sz->dims[0].is) &&
+ split(p->ro, p->io, p->sz->dims[0].n, p->sz->dims[0].os))
+ return 1;
+
+ return !(NO_UGLYP(plnr));
+ }
+}
+
+static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
+{
+ P *pln;
+ const problem_dft *p;
+ plan *cld;
+
+ static const plan_adt padt = {
+ X(dft_solve), awake, print, destroy
+ };
+
+ UNUSED(ego_);
+ if (!applicable(p_, plnr))
+ return (plan *)0;
+
+ p = (const problem_dft *) p_;
+
+ {
+ tensor *ri_vec = X(mktensor_1d)(2, p->ii - p->ri, p->io - p->ro);
+ tensor *cld_vec = X(tensor_append)(ri_vec, p->vecsz);
+ cld = X(mkplan_d)(plnr,
+ X(mkproblem_rdft_1)(p->sz, cld_vec,
+ p->ri, p->ro, R2HC));
+ X(tensor_destroy2)(ri_vec, cld_vec);
+ }
+ if (!cld) return (plan *)0;
+
+ pln = MKPLAN_DFT(P, &padt, apply);
+
+#if ALLOW_RANK0
+ if (p->sz->rnk == 0) {
+ pln->n = 1;
+ pln->os = 0;
+ }
+ else
+#endif
+ {
+ 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 += 8 * ((pln->n - 1)/2);
+ pln->super.super.ops.add += 4 * ((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(dft_r2hc_register)(planner *p)
+{
+ REGISTER_SOLVER(p, mksolver());
+}