GRASS GIS 8 Programmer's Manual 8.2.0(2022)-exported
cmmul.c
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1/* cmmul.c CCMATH mathematics library source code.
2 *
3 * Copyright (C) 2000 Daniel A. Atkinson All rights reserved.
4 * This code may be redistributed under the terms of the GNU library
5 * public license (LGPL). ( See the lgpl.license file for details.)
6 * ------------------------------------------------------------------------
7 */
8#include "ccmath.h"
9void cmmul(Cpx * c, Cpx * a, Cpx * b, int n)
10{
11 Cpx s, *p, *q;
12
13 int i, j, k;
14
15 trncm(b, n);
16 for (i = 0; i < n; ++i, a += n) {
17 for (j = 0, q = b; j < n; ++j) {
18 for (k = 0, p = a, s.re = s.im = 0.; k < n; ++k) {
19 s.re += p->re * q->re - p->im * q->im;
20 s.im += p->im * q->re + p->re * q->im;
21 ++p;
22 ++q;
23 }
24 *c++ = s;
25 }
26 }
27 trncm(b, n);
28}
void trncm(Cpx *a, int n)
Definition: trncm.c:9
void cmmul(Cpx *c, Cpx *a, Cpx *b, int n)
Definition: cmmul.c:9
double b
Definition: ccmath.h:38
double re
Definition: ccmath.h:38
double im
Definition: ccmath.h:38