From 5a422aba704c375a307a902bafe658342e209906 Mon Sep 17 00:00:00 2001 From: scuri Date: Fri, 17 Oct 2008 06:10:15 +0000 Subject: First commit - moving from LuaForge to SourceForge --- src/fftw3/dft/rader-omega.c | 57 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 src/fftw3/dft/rader-omega.c (limited to 'src/fftw3/dft/rader-omega.c') diff --git a/src/fftw3/dft/rader-omega.c b/src/fftw3/dft/rader-omega.c new file mode 100644 index 0000000..7fd86b9 --- /dev/null +++ b/src/fftw3/dft/rader-omega.c @@ -0,0 +1,57 @@ +/* + * 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 + * + */ + +#include "dft.h" + +static rader_tl *omegas = 0; + +R *X(dft_rader_mkomega)(plan *p_, int n, int ginv) +{ + plan_dft *p = (plan_dft *) p_; + R *omega; + int i, gpower; + trigreal scale; + + if ((omega = X(rader_tl_find)(n, n, ginv, omegas))) + return omega; + + omega = (R *)MALLOC(sizeof(R) * (n - 1) * 2, TWIDDLES); + + scale = n - 1.0; /* normalization for convolution */ + + for (i = 0, gpower = 1; i < n-1; ++i, gpower = MULMOD(gpower, ginv, n)) { + omega[2*i] = X(cos2pi)(gpower, n) / scale; + omega[2*i+1] = FFT_SIGN * X(sin2pi)(gpower, n) / scale; + } + A(gpower == 1); + + AWAKE(p_, 1); + p->apply(p_, omega, omega + 1, omega, omega + 1); + AWAKE(p_, 0); + + X(rader_tl_insert)(n, n, ginv, omega, &omegas); + return omega; +} + +void X(dft_rader_free_omega)(R **omega) +{ + X(rader_tl_delete)(*omega, &omegas); + *omega = 0; +} -- cgit v1.2.3