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utrncm.c
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1 /* utrncm.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 utrncm(Cpx * cm, Cpx * a, Cpx * b, int n)
11 {
12  Cpx z, *q0, *p, *s, *t;
13 
14  int i, j, k;
15 
16  q0 = (Cpx *) calloc(n, sizeof(Cpx));
17  for (i = 0; i < n; ++i, ++cm) {
18  for (j = 0, t = b; j < n; ++j) {
19  z.re = z.im = 0.;
20  for (k = 0, s = a + i * n; k < n; ++k, ++s, ++t) {
21  z.re += t->re * s->re + t->im * s->im;
22  z.im += t->im * s->re - t->re * s->im;
23  }
24  q0[j] = z;
25  }
26  for (j = 0, p = cm, t = a; j < n; ++j, p += n) {
27  z.re = z.im = 0.;
28  for (k = 0, s = q0; k < n; ++k, ++t, ++s) {
29  z.re += t->re * s->re - t->im * s->im;
30  z.im += t->im * s->re + t->re * s->im;
31  }
32  *p = z;
33  }
34  }
35  free(q0);
36 }
void utrncm(Cpx *at, Cpx *u, Cpx *a, int n)
Definition: utrncm.c:10
void free(void *)
double t
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