mirror of
https://github.com/VK3FNG/soundmodem.git
synced 2025-12-06 03:01:59 +01:00
77 lines
1.7 KiB
C
77 lines
1.7 KiB
C
/*
|
|
* Matrix operations library
|
|
*
|
|
* Copyright (C) 1999-2000
|
|
* Thomas Sailer, <sailer@ife.ee.ethz.ch>
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
/* AIX requires this to be the first thing in the file. */
|
|
#ifndef __GNUC__
|
|
# if HAVE_ALLOCA_H
|
|
# include <alloca.h>
|
|
# else
|
|
# ifdef _AIX
|
|
#pragma alloca
|
|
# else
|
|
# ifndef alloca /* predefined by HP cc +Olibcalls */
|
|
char *alloca ();
|
|
# endif
|
|
# endif
|
|
# endif
|
|
#endif
|
|
|
|
#include "mat.h"
|
|
|
|
cplxfloat_t fcdet(const cplxfloat_t *c, unsigned int d)
|
|
{
|
|
cplxfloat_t *c2;
|
|
unsigned int i, j, k, l;
|
|
cplxfloat_t det, dr;
|
|
|
|
cplx(det, 0, 0);
|
|
if (!d)
|
|
return det;
|
|
if (d == 1)
|
|
return c[0];
|
|
if (d == 2) {
|
|
cmul(det, c[0], c[3]);
|
|
cmsub(det, c[1], c[2]);
|
|
return det;
|
|
}
|
|
c2 = alloca(sizeof(cplxfloat_t)*(d-1)*(d-1));
|
|
for (i = 0; i < d; i++) {
|
|
for (j = k = 0; j < d; j++) {
|
|
if (j == i)
|
|
continue;
|
|
for (l = 0; l < d-1; l++)
|
|
c2[l*(d-1)+k] = c[(l+1)*d+j];
|
|
k++;
|
|
}
|
|
dr = fcdet(c2, d-1);
|
|
if (i & 1)
|
|
cmsub(det, dr, c[i]);
|
|
else
|
|
cmac(det, dr, c[i]);
|
|
}
|
|
return det;
|
|
}
|
|
|