## File: dht-r2hc.c

package info (click to toggle)
fftw3 3.3.8-2
 `123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144` ``````/* * Copyright (c) 2003, 2007-14 Matteo Frigo * Copyright (c) 2003, 2007-14 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 * */ /* Solve a DHT problem (Discrete Hartley Transform) via post-processing of an R2HC problem. */ #include "rdft/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_, enum wakefulness wakefulness) { P *ego = (P *) ego_; X(plan_awake)(ego->cld, wakefulness); } 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) { 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 ); } static int applicable(const solver *ego, const problem *p, const planner *plnr) { UNUSED(ego); return (!NO_SLOWP(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_; /* NO_DHT_R2HC stops infinite loops with rdft-dht.c */ cld = X(mkplan_f_d)(plnr, X(mkproblem_rdft_1)(p->sz, p->vecsz, p->I, p->O, R2HC), NO_DHT_R2HC, 0, 0); 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 = { PROBLEM_RDFT, mkplan, 0 }; S *slv = MKSOLVER(S, &sadt); return &(slv->super); } void X(dht_r2hc_register)(planner *p) { REGISTER_SOLVER(p, mksolver()); } ``````