| /* |
| * Copyright (c) 2008-2016 Stefan Krah. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| |
| #include "mpdecimal.h" |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <assert.h> |
| #include "bits.h" |
| #include "difradix2.h" |
| #include "numbertheory.h" |
| #include "fnt.h" |
| |
| |
| /* Bignum: Fast transform for medium-sized coefficients. */ |
| |
| |
| /* forward transform, sign = -1 */ |
| int |
| std_fnt(mpd_uint_t *a, mpd_size_t n, int modnum) |
| { |
| struct fnt_params *tparams; |
| |
| assert(ispower2(n)); |
| assert(n >= 4); |
| assert(n <= 3*MPD_MAXTRANSFORM_2N); |
| |
| if ((tparams = _mpd_init_fnt_params(n, -1, modnum)) == NULL) { |
| return 0; |
| } |
| fnt_dif2(a, n, tparams); |
| |
| mpd_free(tparams); |
| return 1; |
| } |
| |
| /* reverse transform, sign = 1 */ |
| int |
| std_inv_fnt(mpd_uint_t *a, mpd_size_t n, int modnum) |
| { |
| struct fnt_params *tparams; |
| |
| assert(ispower2(n)); |
| assert(n >= 4); |
| assert(n <= 3*MPD_MAXTRANSFORM_2N); |
| |
| if ((tparams = _mpd_init_fnt_params(n, 1, modnum)) == NULL) { |
| return 0; |
| } |
| fnt_dif2(a, n, tparams); |
| |
| mpd_free(tparams); |
| return 1; |
| } |
| |
| |
| |