diff options
author | scuri <scuri> | 2009-08-20 12:35:06 +0000 |
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committer | scuri <scuri> | 2009-08-20 12:35:06 +0000 |
commit | 5d735255ddd3cb2f547abd3d03969af3fb7eb04e (patch) | |
tree | 8fb66510bc625bb1b08ccb41f1b83fb0f7cb8f19 /src/fftw3/reodft/reodft010e-r2hc.c | |
parent | 35733b87eed86e5228f12fa10c98a3d9d22a6073 (diff) |
*** empty log message ***
Diffstat (limited to 'src/fftw3/reodft/reodft010e-r2hc.c')
-rw-r--r-- | src/fftw3/reodft/reodft010e-r2hc.c | 409 |
1 files changed, 0 insertions, 409 deletions
diff --git a/src/fftw3/reodft/reodft010e-r2hc.c b/src/fftw3/reodft/reodft010e-r2hc.c deleted file mode 100644 index ace14de..0000000 --- a/src/fftw3/reodft/reodft010e-r2hc.c +++ /dev/null @@ -1,409 +0,0 @@ -/* - * 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: reodft010e-r2hc.c,v 1.1 2008/10/17 06:13:18 scuri Exp $ */ - -/* Do an R{E,O}DFT{01,10} problem via an R2HC problem, with some - pre/post-processing ala FFTPACK. */ - -#include "reodft.h" - -typedef struct { - solver super; -} S; - -typedef struct { - plan_rdft super; - plan *cld; - twid *td; - int is, os; - int n; - int vl; - int ivs, ovs; - rdft_kind kind; -} P; - -/* A real-even-01 DFT operates logically on a size-4N array: - I 0 -r(I*) -I 0 r(I*), - where r denotes reversal and * denotes deletion of the 0th element. - To compute the transform of this, we imagine performing a radix-4 - (real-input) DIF step, which turns the size-4N DFT into 4 size-N - (contiguous) DFTs, two of which are zero and two of which are - conjugates. The non-redundant size-N DFT has halfcomplex input, so - we can do it with a size-N hc2r transform. (In order to share - plans with the re10 (inverse) transform, however, we use the DHT - trick to re-express the hc2r problem as r2hc. This has little cost - since we are already pre- and post-processing the data in {i,n-i} - order.) Finally, we have to write out the data in the correct - order...the two size-N redundant (conjugate) hc2r DFTs correspond - to the even and odd outputs in O (i.e. the usual interleaved output - of DIF transforms); since this data has even symmetry, we only - write the first half of it. - - The real-even-10 DFT is just the reverse of these steps, i.e. a - radix-4 DIT transform. There, however, we just use the r2hc - transform naturally without resorting to the DHT trick. - - A real-odd-01 DFT is very similar, except that the input is - 0 I (rI)* 0 -I -(rI)*. This format, however, can be transformed - into precisely the real-even-01 format above by sending I -> rI - and shifting the array by N. The former swap is just another - transformation on the input during preprocessing; the latter - multiplies the even/odd outputs by i/-i, which combines with - the factor of -i (to take the imaginary part) to simply flip - the sign of the odd outputs. Vice-versa for real-odd-10. - - The FFTPACK source code was very helpful in working this out. - (They do unnecessary passes over the array, though.) - - Note that Numerical Recipes suggests a different algorithm that - requires more operations and uses trig. functions for both the pre- - and post-processing passes. -*/ - -static void apply_re01(const plan *ego_, R *I, R *O) -{ - const P *ego = (const P *) ego_; - int is = ego->is, os = ego->os; - int i, n = ego->n; - int iv, vl = ego->vl; - int ivs = ego->ivs, ovs = ego->ovs; - R *W = ego->td->W; - R *buf; - - buf = (R *) MALLOC(sizeof(R) * n, BUFFERS); - - for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) { - buf[0] = I[0]; - for (i = 1; i < n - i; ++i) { - E a, b, apb, amb, wa, wb; - a = I[is * i]; - b = I[is * (n - i)]; - apb = a + b; - amb = a - b; - wa = W[2*i]; - wb = W[2*i + 1]; - buf[i] = wa * amb + wb * apb; - buf[n - i] = wa * apb - wb * amb; - } - if (i == n - i) { - buf[i] = K(2.0) * I[is * i] * W[2*i]; - } - - { - plan_rdft *cld = (plan_rdft *) ego->cld; - cld->apply((plan *) cld, buf, buf); - } - - O[0] = buf[0]; - for (i = 1; i < n - i; ++i) { - E a, b; - int k; - a = buf[i]; - b = buf[n - i]; - k = i + i; - O[os * (k - 1)] = a - b; - O[os * k] = a + b; - } - if (i == n - i) { - O[os * (n - 1)] = buf[i]; - } - } - - X(ifree)(buf); -} - -/* ro01 is same as re01, but with i <-> n - 1 - i in the input and - the sign of the odd output elements flipped. */ -static void apply_ro01(const plan *ego_, R *I, R *O) -{ - const P *ego = (const P *) ego_; - int is = ego->is, os = ego->os; - int i, n = ego->n; - int iv, vl = ego->vl; - int ivs = ego->ivs, ovs = ego->ovs; - R *W = ego->td->W; - R *buf; - - buf = (R *) MALLOC(sizeof(R) * n, BUFFERS); - - for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) { - buf[0] = I[is * (n - 1)]; - for (i = 1; i < n - i; ++i) { - E a, b, apb, amb, wa, wb; - a = I[is * (n - 1 - i)]; - b = I[is * (i - 1)]; - apb = a + b; - amb = a - b; - wa = W[2*i]; - wb = W[2*i+1]; - buf[i] = wa * amb + wb * apb; - buf[n - i] = wa * apb - wb * amb; - } - if (i == n - i) { - buf[i] = K(2.0) * I[is * (i - 1)] * W[2*i]; - } - - { - plan_rdft *cld = (plan_rdft *) ego->cld; - cld->apply((plan *) cld, buf, buf); - } - - O[0] = buf[0]; - for (i = 1; i < n - i; ++i) { - E a, b; - int k; - a = buf[i]; - b = buf[n - i]; - k = i + i; - O[os * (k - 1)] = b - a; - O[os * k] = a + b; - } - if (i == n - i) { - O[os * (n - 1)] = -buf[i]; - } - } - - X(ifree)(buf); -} - -static void apply_re10(const plan *ego_, R *I, R *O) -{ - const P *ego = (const P *) ego_; - int is = ego->is, os = ego->os; - int i, n = ego->n; - int iv, vl = ego->vl; - int ivs = ego->ivs, ovs = ego->ovs; - R *W = ego->td->W; - R *buf; - - buf = (R *) MALLOC(sizeof(R) * n, BUFFERS); - - for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) { - buf[0] = I[0]; - for (i = 1; i < n - i; ++i) { - E u, v; - int k = i + i; - u = I[is * (k - 1)]; - v = I[is * k]; - buf[n - i] = u; - buf[i] = v; - } - if (i == n - i) { - buf[i] = I[is * (n - 1)]; - } - - { - plan_rdft *cld = (plan_rdft *) ego->cld; - cld->apply((plan *) cld, buf, buf); - } - - O[0] = K(2.0) * buf[0]; - for (i = 1; i < n - i; ++i) { - E a, b, wa, wb; - a = K(2.0) * buf[i]; - b = K(2.0) * buf[n - i]; - wa = W[2*i]; - wb = W[2*i + 1]; - O[os * i] = wa * a + wb * b; - O[os * (n - i)] = wb * a - wa * b; - } - if (i == n - i) { - O[os * i] = K(2.0) * buf[i] * W[2*i]; - } - } - - X(ifree)(buf); -} - -/* ro10 is same as re10, but with i <-> n - 1 - i in the output and - the sign of the odd input elements flipped. */ -static void apply_ro10(const plan *ego_, R *I, R *O) -{ - const P *ego = (const P *) ego_; - int is = ego->is, os = ego->os; - int i, n = ego->n; - int iv, vl = ego->vl; - int ivs = ego->ivs, ovs = ego->ovs; - R *W = ego->td->W; - R *buf; - - buf = (R *) MALLOC(sizeof(R) * n, BUFFERS); - - for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) { - buf[0] = I[0]; - for (i = 1; i < n - i; ++i) { - E u, v; - int k = i + i; - u = -I[is * (k - 1)]; - v = I[is * k]; - buf[n - i] = u; - buf[i] = v; - } - if (i == n - i) { - buf[i] = -I[is * (n - 1)]; - } - - { - plan_rdft *cld = (plan_rdft *) ego->cld; - cld->apply((plan *) cld, buf, buf); - } - - O[os * (n - 1)] = K(2.0) * buf[0]; - for (i = 1; i < n - i; ++i) { - E a, b, wa, wb; - a = K(2.0) * buf[i]; - b = K(2.0) * buf[n - i]; - wa = W[2*i]; - wb = W[2*i + 1]; - O[os * (n - 1 - i)] = wa * a + wb * b; - O[os * (i - 1)] = wb * a - wa * b; - } - if (i == n - i) { - O[os * (i - 1)] = K(2.0) * buf[i] * W[2*i]; - } - } - - X(ifree)(buf); -} - -static void awake(plan *ego_, int flg) -{ - P *ego = (P *) ego_; - static const tw_instr reodft010e_tw[] = { - { TW_COS, 0, 1 }, - { TW_SIN, 0, 1 }, - { TW_NEXT, 1, 0 } - }; - - AWAKE(ego->cld, flg); - - X(twiddle_awake)(flg, &ego->td, reodft010e_tw, 4*ego->n, 1, ego->n/2+1); -} - -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, "(%se-r2hc-%d%v%(%p%))", - X(rdft_kind_str)(ego->kind), ego->n, ego->vl, ego->cld); -} - -static int applicable0(const solver *ego_, const problem *p_) -{ - UNUSED(ego_); - if (RDFTP(p_)) { - const problem_rdft *p = (const problem_rdft *) p_; - return (1 - && p->sz->rnk == 1 - && p->vecsz->rnk <= 1 - && (p->kind[0] == REDFT01 || p->kind[0] == REDFT10 - || p->kind[0] == RODFT01 || p->kind[0] == RODFT10) - ); - } - - return 0; -} - -static int applicable(const solver *ego, const problem *p, const planner *plnr) -{ - return (!NO_UGLYP(plnr) && applicable0(ego, p)); -} - -static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr) -{ - P *pln; - const problem_rdft *p; - plan *cld; - R *buf; - int n; - opcnt ops; - - static const plan_adt padt = { - X(rdft_solve), awake, print, destroy - }; - - if (!applicable(ego_, p_, plnr)) - return (plan *)0; - - p = (const problem_rdft *) p_; - - n = p->sz->dims[0].n; - buf = (R *) MALLOC(sizeof(R) * n, BUFFERS); - - cld = X(mkplan_d)(plnr, X(mkproblem_rdft_1_d)(X(mktensor_1d)(n, 1, 1), - X(mktensor_0d)(), - buf, buf, R2HC)); - X(ifree)(buf); - if (!cld) - return (plan *)0; - - switch (p->kind[0]) { - case REDFT01: pln = MKPLAN_RDFT(P, &padt, apply_re01); break; - case REDFT10: pln = MKPLAN_RDFT(P, &padt, apply_re10); break; - case RODFT01: pln = MKPLAN_RDFT(P, &padt, apply_ro01); break; - case RODFT10: pln = MKPLAN_RDFT(P, &padt, apply_ro10); break; - default: A(0); return (plan*)0; - } - - pln->n = n; - pln->is = p->sz->dims[0].is; - pln->os = p->sz->dims[0].os; - pln->cld = cld; - pln->td = 0; - pln->kind = p->kind[0]; - - X(tensor_tornk1)(p->vecsz, &pln->vl, &pln->ivs, &pln->ovs); - - X(ops_zero)(&ops); - ops.other = 4 + (n-1)/2 * 10 + (1 - n % 2) * 5; - if (p->kind[0] == REDFT01 || p->kind[0] == RODFT01) { - ops.add = (n-1)/2 * 6; - ops.mul = (n-1)/2 * 4 + (1 - n % 2) * 2; - } - else { /* 10 transforms */ - ops.add = (n-1)/2 * 2; - ops.mul = 1 + (n-1)/2 * 6 + (1 - n % 2) * 2; - } - - 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); - - 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(reodft010e_r2hc_register)(planner *p) -{ - REGISTER_SOLVER(p, mksolver()); -} |