diff src/fftw-3.3.3/reodft/redft00e-r2hc-pad.c @ 10:37bf6b4a2645

Add FFTW3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/fftw-3.3.3/reodft/redft00e-r2hc-pad.c	Wed Mar 20 15:35:50 2013 +0000
@@ -0,0 +1,197 @@
+/*
+ * Copyright (c) 2003, 2007-11 Matteo Frigo
+ * Copyright (c) 2003, 2007-11 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+
+/* Do a REDFT00 problem via an R2HC problem, padded symmetrically to
+   twice the size.  This is asymptotically a factor of ~2 worse than
+   redft00e-r2hc.c (the algorithm used in e.g. FFTPACK and Numerical
+   Recipes), but we abandoned the latter after we discovered that it
+   has intrinsic accuracy problems. */
+
+#include "reodft.h"
+
+typedef struct {
+     solver super;
+} S;
+
+typedef struct {
+     plan_rdft super;
+     plan *cld, *cldcpy;
+     INT is;
+     INT n;
+     INT vl;
+     INT ivs, ovs;
+} P;
+
+static void apply(const plan *ego_, R *I, R *O)
+{
+     const P *ego = (const P *) ego_;
+     INT is = ego->is;
+     INT i, n = ego->n;
+     INT iv, vl = ego->vl;
+     INT ivs = ego->ivs, ovs = ego->ovs;
+     R *buf;
+
+     buf = (R *) MALLOC(sizeof(R) * (2*n), BUFFERS);
+
+     for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) {
+	  buf[0] = I[0];
+	  for (i = 1; i < n; ++i) {
+	       R a = I[i * is];
+	       buf[i] = a;
+	       buf[2*n - i] = a;
+	  }
+	  buf[i] = I[i * is]; /* i == n, Nyquist */
+	  
+	  /* r2hc transform of size 2*n */
+	  {
+	       plan_rdft *cld = (plan_rdft *) ego->cld;
+	       cld->apply((plan *) cld, buf, buf);
+	  }
+	  
+	  /* copy n+1 real numbers (real parts of hc array) from buf to O */
+	  {
+	       plan_rdft *cldcpy = (plan_rdft *) ego->cldcpy;
+	       cldcpy->apply((plan *) cldcpy, buf, O);
+	  }
+     }
+
+     X(ifree)(buf);
+}
+
+static void awake(plan *ego_, enum wakefulness wakefulness)
+{
+     P *ego = (P *) ego_;
+     X(plan_awake)(ego->cld, wakefulness);
+     X(plan_awake)(ego->cldcpy, wakefulness);
+}
+
+static void destroy(plan *ego_)
+{
+     P *ego = (P *) ego_;
+     X(plan_destroy_internal)(ego->cldcpy);
+     X(plan_destroy_internal)(ego->cld);
+}
+
+static void print(const plan *ego_, printer *p)
+{
+     const P *ego = (const P *) ego_;
+     p->print(p, "(redft00e-r2hc-pad-%D%v%(%p%)%(%p%))", 
+	      ego->n + 1, ego->vl, ego->cld, ego->cldcpy);
+}
+
+static int applicable0(const solver *ego_, const problem *p_)
+{
+     const problem_rdft *p = (const problem_rdft *) p_;
+     UNUSED(ego_);
+
+     return (1
+	     && p->sz->rnk == 1
+	     && p->vecsz->rnk <= 1
+	     && p->kind[0] == REDFT00
+	     && p->sz->dims[0].n > 1  /* n == 1 is not well-defined */
+	  );
+}
+
+static int applicable(const solver *ego, const problem *p, const planner *plnr)
+{
+     return (!NO_SLOWP(plnr) && applicable0(ego, p));
+}
+
+static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
+{
+     P *pln;
+     const problem_rdft *p;
+     plan *cld = (plan *) 0, *cldcpy;
+     R *buf = (R *) 0;
+     INT n;
+     INT vl, ivs, ovs;
+     opcnt ops;
+
+     static const plan_adt padt = {
+	  X(rdft_solve), awake, print, destroy
+     };
+
+     if (!applicable(ego_, p_, plnr))
+	  goto nada;
+
+     p = (const problem_rdft *) p_;
+
+     n = p->sz->dims[0].n - 1;
+     A(n > 0);
+     buf = (R *) MALLOC(sizeof(R) * (2*n), BUFFERS);
+
+     cld = X(mkplan_d)(plnr,X(mkproblem_rdft_1_d)(X(mktensor_1d)(2*n,1,1), 
+						  X(mktensor_0d)(), 
+						  buf, buf, R2HC));
+     if (!cld)
+	  goto nada;
+
+     X(tensor_tornk1)(p->vecsz, &vl, &ivs, &ovs);
+     cldcpy =
+	  X(mkplan_d)(plnr,
+		      X(mkproblem_rdft_1_d)(X(mktensor_0d)(),
+					    X(mktensor_1d)(n+1,1,
+							   p->sz->dims[0].os), 
+					    buf, TAINT(p->O, ovs), R2HC));
+     if (!cldcpy)
+	  goto nada;
+
+     X(ifree)(buf);
+
+     pln = MKPLAN_RDFT(P, &padt, apply);
+
+     pln->n = n;
+     pln->is = p->sz->dims[0].is;
+     pln->cld = cld;
+     pln->cldcpy = cldcpy;
+     pln->vl = vl;
+     pln->ivs = ivs;
+     pln->ovs = ovs;
+     
+     X(ops_zero)(&ops);
+     ops.other = n + 2*n; /* loads + stores (input -> buf) */
+
+     X(ops_zero)(&pln->super.super.ops);
+     X(ops_madd2)(pln->vl, &ops, &pln->super.super.ops);
+     X(ops_madd2)(pln->vl, &cld->ops, &pln->super.super.ops);
+     X(ops_madd2)(pln->vl, &cldcpy->ops, &pln->super.super.ops);
+
+     return &(pln->super.super);
+
+ nada:
+     X(ifree0)(buf);
+     if (cld)
+	  X(plan_destroy_internal)(cld);  
+     return (plan *)0;
+}
+
+/* constructor */
+static solver *mksolver(void)
+{
+     static const solver_adt sadt = { PROBLEM_RDFT, mkplan, 0 };
+     S *slv = MKSOLVER(S, &sadt);
+     return &(slv->super);
+}
+
+void X(redft00e_r2hc_pad_register)(planner *p)
+{
+     REGISTER_SOLVER(p, mksolver());
+}