GRASS GIS 7 Programmer's Manual  7.7.svn(2018)-r73600
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cmmult.c
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1 /* cmmult.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 <stdlib.h>
9 #include "ccmath.h"
10 void cmmult(Cpx * cm, Cpx * a, Cpx * b, int n, int m, int l)
11 {
12  Cpx z, *q0, *p, *q;
13 
14  int i, j, k;
15 
16  q0 = (Cpx *) calloc(m, sizeof(Cpx));
17  for (i = 0; i < l; ++i, ++cm) {
18  for (k = 0, p = b + i; k < m; p += l)
19  q0[k++] = *p;
20  for (j = 0, p = a, q = cm; j < n; ++j, q += l) {
21  for (k = 0, z.re = z.im = 0.; k < m; ++k, ++p) {
22  z.re += p->re * q0[k].re - p->im * q0[k].im;
23  z.im += p->im * q0[k].re + p->re * q0[k].im;
24  }
25  *q = z;
26  }
27  }
28  free(q0);
29 }
void free(void *)
void cmmult(Cpx *c, Cpx *a, Cpx *b, int m, int k, int n)
Definition: cmmult.c:10
double l
Definition: r_raster.c:39
double b
Definition: r_raster.c:39
double re
Definition: ccmath.h:38
double im
Definition: ccmath.h:38
Definition: la.h:54