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38 /* This file is completely threadsafe - keep it that way! */
48 #include "gmx_fatal.h"
53 void do_rotate(double **a, int i, int j, int k, int l, double tau, double s)
58 a[i][j] = g - s * (h + g * tau);
59 a[k][l] = h + s * (g - h * tau);
62 void jacobi(double **a,int n,double d[],double **v,int *nrot)
66 double tresh,theta,tau,t,sm,s,h,g,c,*b,*z;
70 for (ip=0; ip<n; ip++) {
71 for (iq=0; iq<n; iq++) v[ip][iq]=0.0;
74 for (ip=0; ip<n;ip++) {
75 b[ip]=d[ip]=a[ip][ip];
79 for (i=1; i<=50; i++) {
81 for (ip=0; ip<n-1; ip++) {
82 for (iq=ip+1; iq<n; iq++)
83 sm += fabs(a[ip][iq]);
94 for (ip=0; ip<n-1; ip++) {
95 for (iq=ip+1; iq<n; iq++) {
96 g=100.0*fabs(a[ip][iq]);
97 if (i > 4 && fabs(d[ip])+g == fabs(d[ip])
98 && fabs(d[iq])+g == fabs(d[iq]))
100 else if (fabs(a[ip][iq]) > tresh) {
102 if (fabs(h)+g == fabs(h))
105 theta=0.5*h/(a[ip][iq]);
106 t=1.0/(fabs(theta)+sqrt(1.0+theta*theta));
107 if (theta < 0.0) t = -t;
120 do_rotate(a,j,ip,j,iq,tau,s);
122 for (j=ip+1; j<iq; j++)
124 do_rotate(a,ip,j,j,iq,tau,s);
126 for (j=iq+1; j<n; j++)
128 do_rotate(a,ip,j,iq,j,tau,s);
132 do_rotate(v,j,ip,j,iq,tau,s);
138 for (ip=0; ip<n; ip++) {
144 gmx_fatal(FARGS,"Error: Too many iterations in routine JACOBI\n");
147 int m_inv_gen(real **m,int n,real **minv)
149 double **md,**v,*eig,tol,s;
150 int nzero,i,j,k,nrot;
165 tol += fabs(md[i][i]);
168 jacobi(md,n,eig,v,&nrot);
172 if (fabs(eig[i]) < tol) {
182 s += eig[k]*v[i][k]*v[j][k];