1
/* chousv.c CCMATH mathematics library source code.
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
* ------------------------------------------------------------------------
10
void chousv(Cpx * a, double *d, double *dp, int n)
20
qs = (Cpx *) calloc(2 * n, sizeof(Cpx));
22
for (j = 0, pc = a; j < n - 2; ++j, pc += n + 1, ++q) {
24
for (i = 1, sc = 0.; i <= m; ++i)
25
sc += pc[i].re * pc[i].re + pc[i].im * pc[i].im;
29
y = sc + (x = sqrt(p->re * p->re + p->im * p->im));
40
x = 1. / sqrt(2. * sc * y);
42
for (i = 0, qw = pc + 1; i < m; ++i) {
43
qs[i].re = qs[i].im = 0.;
50
qw[0].im = -y * cc.im;
53
for (i = 0, e = j + 2, p = pc + n + 1, y = 0.; i < m;
55
qs[i].re += (u.re = qw[i].re) * p->re - (u.im =
57
qs[i].im += u.re * p->im + u.im * p->re;
59
for (k = i + 1; k < m; ++k, ++p) {
60
qs[i].re += qw[k].re * p->re - qw[k].im * p->im;
61
qs[i].im += qw[k].im * p->re + qw[k].re * p->im;
62
qs[k].re += u.re * p->re + u.im * p->im;
63
qs[k].im += u.im * p->re - u.re * p->im;
65
y += u.re * qs[i].re + u.im * qs[i].im;
67
for (i = 0; i < m; ++i) {
68
qs[i].re -= y * qw[i].re;
70
qs[i].im -= y * qw[i].im;
73
for (i = 0, e = j + 2, p = pc + n + 1; i < m; ++i, p += e++) {
74
for (k = i; k < m; ++k, ++p) {
75
p->re -= qw[i].re * qs[k].re + qw[i].im * qs[k].im
76
+ qs[i].re * qw[k].re + qs[i].im * qw[k].im;
77
p->im -= qw[i].im * qs[k].re - qw[i].re * qs[k].im
78
+ qs[i].im * qw[k].re - qs[i].re * qw[k].im;
87
d[j + 1] = (pc += n + 1)->re;
88
dp[j] = sc = sqrt(cc.re * cc.re + cc.im * cc.im);
91
for (i = 0, m = n + n, p = pc; i < m; ++i, --p)
94
(pc -= n + 1)->re = 1.;
96
for (m = 2; m < n; ++m, qw -= n + 1) {
97
for (j = 0, p = pc, pc->re = 1.; j < m; ++j, p += n) {
98
for (i = 0, q = p, u.re = u.im = 0.; i < m; ++i, ++q) {
99
u.re += qw[i].re * q->re - qw[i].im * q->im;
100
u.im += qw[i].re * q->im + qw[i].im * q->re;
102
for (i = 0, q = p, u.re += u.re, u.im += u.im; i < m; ++i, ++q) {
103
q->re -= u.re * qw[i].re + u.im * qw[i].im;
104
q->im -= u.im * qw[i].re - u.re * qw[i].im;
107
for (i = 0, p = qw + m - 1; i < n; ++i, --p)
109
(pc -= n + 1)->re = 1.;
111
for (j = 1, p = a + n + 1, q = qs + n, u.re = 1., u.im = 0.; j < n;
113
sc = u.re * q->re - u.im * q->im;
114
u.im = u.im * q->re + u.re * q->im;
116
for (i = 1; i < n; ++i, ++p) {
117
sc = u.re * p->re - u.im * p->im;
118
p->im = u.re * p->im + u.im * p->re;