Rev 3 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | pj | 1 | /* |
| 2 | * Copyright (c) 1997-1999 Massachusetts Institute of Technology |
||
| 3 | * |
||
| 4 | * This program is free software; you can redistribute it and/or modify |
||
| 5 | * it under the terms of the GNU General Public License as published by |
||
| 6 | * the Free Software Foundation; either version 2 of the License, or |
||
| 7 | * (at your option) any later version. |
||
| 8 | * |
||
| 9 | * This program is distributed in the hope that it will be useful, |
||
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
||
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
||
| 12 | * GNU General Public License for more details. |
||
| 13 | * |
||
| 14 | * You should have received a copy of the GNU General Public License |
||
| 15 | * along with this program; if not, write to the Free Software |
||
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
||
| 17 | * |
||
| 18 | */ |
||
| 19 | |||
| 20 | /* |
||
| 21 | * |
||
| 22 | * generic.c -- "generic" codelets. They work for all n (and they are |
||
| 23 | * slow) |
||
| 24 | */ |
||
| 107 | pj | 25 | #include <fftw-int.h> |
| 2 | pj | 26 | #include <stdlib.h> |
| 27 | |||
| 28 | void fftw_twiddle_generic(fftw_complex *A, const fftw_complex *W, |
||
| 29 | int m, int r, int n, int stride) |
||
| 30 | { |
||
| 31 | int i, j, k; |
||
| 32 | const fftw_complex *jp; |
||
| 33 | fftw_complex *kp; |
||
| 34 | fftw_complex *tmp = (fftw_complex *) |
||
| 35 | fftw_malloc(r * sizeof(fftw_complex)); |
||
| 36 | |||
| 37 | for (i = 0; i < m; ++i) { |
||
| 38 | for (k = 0, kp = tmp; k < r; ++k, kp++) { |
||
| 39 | fftw_real r0, i0, rt, it, rw, iw; |
||
| 40 | int l1 = i + m * k; |
||
| 41 | int l0; |
||
| 42 | |||
| 43 | r0 = i0 = 0.0; |
||
| 44 | for (j = 0, jp = A + i * stride, l0 = 0; j < r; ++j, |
||
| 45 | jp += m * stride) { |
||
| 46 | rw = c_re(W[l0]); |
||
| 47 | iw = c_im(W[l0]); |
||
| 48 | rt = c_re(*jp); |
||
| 49 | it = c_im(*jp); |
||
| 50 | r0 += rt * rw - it * iw; |
||
| 51 | i0 += rt * iw + it * rw; |
||
| 52 | l0 += l1; |
||
| 53 | if (l0 >= n) |
||
| 54 | l0 -= n; |
||
| 55 | } |
||
| 56 | c_re(*kp) = r0; |
||
| 57 | c_im(*kp) = i0; |
||
| 58 | } |
||
| 59 | for (k = 0, kp = A + i * stride; k < r; ++k, kp += m * stride) |
||
| 60 | *kp = tmp[k]; |
||
| 61 | } |
||
| 62 | |||
| 63 | fftw_free(tmp); |
||
| 64 | } |
||
| 65 | |||
| 66 | void fftwi_twiddle_generic(fftw_complex *A, const fftw_complex *W, |
||
| 67 | int m, int r, int n, int stride) |
||
| 68 | { |
||
| 69 | int i, j, k; |
||
| 70 | const fftw_complex *jp; |
||
| 71 | fftw_complex *kp; |
||
| 72 | fftw_complex *tmp = (fftw_complex *) |
||
| 73 | fftw_malloc(r * sizeof(fftw_complex)); |
||
| 74 | |||
| 75 | for (i = 0; i < m; ++i) { |
||
| 76 | for (k = 0, kp = tmp; k < r; ++k, kp++) { |
||
| 77 | fftw_real r0, i0, rt, it, rw, iw; |
||
| 78 | int l1 = i + m * k; |
||
| 79 | int l0; |
||
| 80 | |||
| 81 | r0 = i0 = 0.0; |
||
| 82 | for (j = 0, jp = A + i * stride, l0 = 0; j < r; ++j, |
||
| 83 | jp += m * stride) { |
||
| 84 | rw = c_re(W[l0]); |
||
| 85 | iw = c_im(W[l0]); |
||
| 86 | rt = c_re(*jp); |
||
| 87 | it = c_im(*jp); |
||
| 88 | r0 += rt * rw + it * iw; |
||
| 89 | i0 += it * rw - rt * iw; |
||
| 90 | l0 += l1; |
||
| 91 | if (l0 >= n) |
||
| 92 | l0 -= n; |
||
| 93 | } |
||
| 94 | c_re(*kp) = r0; |
||
| 95 | c_im(*kp) = i0; |
||
| 96 | } |
||
| 97 | for (k = 0, kp = A + i * stride; k < r; ++k, kp += m * stride) |
||
| 98 | *kp = tmp[k]; |
||
| 99 | } |
||
| 100 | |||
| 101 | fftw_free(tmp); |
||
| 102 | } |