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36 #include "gmx_lapack.h"
37 #include "lapack_limits.h"
39 #include <types/simple.h>
42 F77_FUNC(dlartg,DLARTG)(double *f,
48 double minval,safemin, safemin2, safemx2, eps;
49 double f1,g1,f1a,g1a,scale;
53 minval = GMX_DOUBLE_MIN;
54 safemin = minval*(1.0+eps);
55 n = 0.5*log( safemin/eps ) / log(2);
58 safemx2 = 1.0 / safemin2;
60 if(fabs(*g)<GMX_DOUBLE_MIN) {
64 } else if (fabs(*f)<GMX_DOUBLE_MIN) {
73 scale = (f1a > g1a) ? f1a : g1a;
74 if(scale >= safemx2) {
76 while(scale >= safemx2) {
82 scale = (f1a > g1a) ? f1a : g1a;
84 *r = sqrt(f1*f1 + g1*g1);
89 } else if (scale<=safemin2) {
91 while(scale <= safemin2) {
97 scale = (f1a > g1a) ? f1a : g1a;
99 *r = sqrt(f1*f1 + g1*g1);
105 *r = sqrt(f1*f1 + g1*g1);
109 if(fabs(*f)>fabs(*g) && *cs<0.0) {