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36 #include <types/simple.h>
38 #include "gmx_lapack.h"
42 F77_FUNC(dlaev2,DLAEV2)(double * a,
52 double ab, df, cs, ct, tb, sm, tn, rt, adf, acs;
61 if (fabs(*a) > fabs(*c__)) {
70 rt = adf * sqrt(d__1 * d__1 + 1.);
71 } else if (adf < ab) {
73 rt = ab * sqrt(d__1 * d__1 + 1.);
79 *rt1 = (sm - rt) * .5;
82 *rt2 = acmx / *rt1 * acmn - *b / *rt1 * *b;
84 *rt1 = (sm + rt) * .5;
86 *rt2 = acmx / *rt1 * acmn - *b / *rt1 * *b;
102 *sn1 = 1. / sqrt(ct * ct + 1.);
105 if (fabs(ab)<GMX_DOUBLE_MIN) {
110 *cs1 = 1. / sqrt(tn * tn + 1.);