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38 #include <types/simple.h>
41 #include "gmx_lapack.h"
44 F77_FUNC(ssytd2,SSYTD2)(const char * uplo,
56 const char ch=toupper(*uplo);
65 for(i=*n-1;i>=1;i--) {
68 F77_FUNC(slarfg,SLARFG)(&i,&(a[i*(*lda)+(i-1)]),&(a[i*(*lda)+0]),&ti1,&taui);
69 e[i-1] = a[i*(*lda) + (i-1)];
70 if(fabs(taui)>GMX_FLOAT_MIN) {
71 a[i*(*lda)+(i-1)] = 1.0;
74 F77_FUNC(ssymv,SSYMV)("U",&i,&taui,a,lda,&(a[i*(*lda)+0]),&ti1,&zero,tau,&ti1);
76 tmp = F77_FUNC(sdot,SDOT)(&i,tau,&ti1,&(a[i*(*lda)+0]),&ti1);
78 alpha = -0.5*taui*tmp;
80 F77_FUNC(saxpy,SAXPY)(&i,&alpha,&(a[i*(*lda)+0]),&ti1,tau,&ti1);
82 F77_FUNC(ssyr2,SSYR2)("U",&i,&minusone,&(a[i*(*lda)+0]),&ti1,tau,&ti1,a,lda);
84 a[i*(*lda)+(i-1)] = e[i-1];
98 ti2 = ( *n < i+2) ? *n : i+2;
100 F77_FUNC(slarfg,SLARFG)(&ti1,&(a[(i-1)*(*lda)+(i)]),&(a[(i-1)*(*lda)+ti2-1]),&ti3,&taui);
102 e[i-1] = a[(i-1)*(*lda) + (i)];
104 if(fabs(taui)>GMX_FLOAT_MIN) {
105 a[(i-1)*(*lda)+(i)] = 1.0;
109 F77_FUNC(ssymv,SSYMV)(uplo,&ti1,&taui,&(a[i*(*lda)+i]),lda,&(a[(i-1)*(*lda)+i]),
110 &ti2,&zero,&(tau[i-1]),&ti2);
112 tmp = F77_FUNC(sdot,SDOT)(&ti1,&(tau[i-1]),&ti2,&(a[(i-1)*(*lda)+i]),&ti2);
114 alpha = -0.5*taui*tmp;
116 F77_FUNC(saxpy,SAXPY)(&ti1,&alpha,&(a[(i-1)*(*lda)+i]),&ti2,&(tau[i-1]),&ti2);
118 F77_FUNC(ssyr2,SSYR2)(uplo,&ti1,&minusone,&(a[(i-1)*(*lda)+i]),&ti2,&(tau[i-1]),&ti2,
119 &(a[(i)*(*lda)+i]),lda);
121 a[(i-1)*(*lda)+(i)] = e[i-1];
124 d[i-1] = a[(i-1)*(*lda)+i-1];
127 d[*n-1] = a[(*n-1)*(*lda)+(*n-1)];