int get_ixyz(double lat[3][3], double cutoff)
{
int i, j, ixyz;
int n = 3, lda = 3, info, lwork;
double* work;
double wkopt, w[3], a[9], lat2[3][3];
lwork = -1;
for (i=0; i < 3; i++)
for (j=0; j < 3; j++)
lat2[i][j] = lat[i][0]*lat[j][0] + lat[i][1]*lat[j][1] + lat[i][2]*lat[j][2];
for (i = 0; i < 3; i++)
for (j = 0; j < 3; j++)
a[i*3+j] = lat2[j][i];
dsyev("V", "U", &n, a, &lda, w, &wkopt, &lwork, &info);
lwork = (int)wkopt;
work = (double*) malloc(lwork*sizeof(double));
dsyev("V", "U", &n, a, &lda, w, work, &lwork, &info);
if (info > 0 ) {
fprintf(stderr, "Error: DSYEV ixyz");
exit(1);
}
ixyz = (int)(sqrt(1.0/w[0])*cutoff + 1);
free(work);
return ixyz;
}
void get_fp(int flag, int nat, int ntyp, int ixyz, int nx, int lseg, int l, double lat[3][3],
double rxyz[][3], int types[], double rcov[], double cutoff, double **lfp, double **sfp)
{
int iat, jat, ix, iy, iz, il, i, j;
int n_sphere, ityp_sphere, nid, nids = l*(ntyp+1);
int n_sphere_min = 1000000;
int n_sphere_max = 0;
int ind[nx*lseg];
double xi, yi, zi, xj, yj, zj, d2;
double cutoff2 = cutoff*cutoff;
double rxyz_sphere[nx][3];
double rcov_sphere[nx];
double amp[nx];
double fc, wc;
double **om, *pvec;
double omx[nids][nids], omy[nids][nids];
int lda, info, lwork;
double wkopt;
double *work, *w, *a;
wc = cutoff / sqrt(2.0 * NC);
fc = 1.0 / (2.0 * NC * wc * wc);
for (iat = 0; iat < nat; iat++) {
xi = rxyz[iat][0];
yi = rxyz[iat][1];
zi = rxyz[iat][2];
n_sphere = 0;
for (jat = 0; jat < nat; jat++) {
for (ix = -ixyz; ix <= ixyz; ix++) {
for (iy = -ixyz; iy <= ixyz; iy++) {
for (iz = -ixyz; iz <= ixyz; iz++) {
xj = rxyz[jat][0] + ix*lat[0][0] + iy*lat[1][0] + iz*lat[2][0];
yj = rxyz[jat][1] + ix*lat[0][1] + iy*lat[1][1] + iz*lat[2][1];
zj = rxyz[jat][2] + ix*lat[0][2] + iy*lat[1][2] + iz*lat[2][2];
d2 = (xj-xi)*(xj-xi) + (yj-yi)*(yj-yi) + (zj-zi)*(zj-zi);
if (d2 <= cutoff2) {
n_sphere++;
if (n_sphere > nx) {
fprintf(stderr, "Error: cutoff is too large.");
exit(1);
}
amp[n_sphere-1] = pow((1.0 - d2*fc), NC);
rxyz_sphere[n_sphere-1][0] = xj;
rxyz_sphere[n_sphere-1][1] = yj;
rxyz_sphere[n_sphere-1][2] = zj;
rcov_sphere[n_sphere-1] = rcov[jat];
if (jat == iat && ix == 0 && iy == 0 && iz == 0) {
ityp_sphere = 0;
} else {
ityp_sphere = types[jat];
}
for (il = 0; il < lseg; il++) {
if (il == 0){
ind[il+lseg*(n_sphere-1)] = ityp_sphere * l + 0;
} else {
ind[il+lseg*(n_sphere-1)] = ityp_sphere * l + 1;
}
}
}
}
}
}
}
n_sphere_min = MIN(n_sphere_min, n_sphere);
n_sphere_max = MAX(n_sphere_max, n_sphere);
// big overlap matrix
nid = lseg * n_sphere;
if ( (om = (double **) malloc(sizeof(double)*nid)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);
}
for (i = 0; i < nid; i++){
if ( (om[i] = (double *) malloc(sizeof(double)*nid)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);
}
}
if ( (pvec = (double *) malloc(sizeof(double)*nid)) == NULL ){
fprintf(stderr, "Memory could not be allocated.");
exit(1);}
creat_om( lseg, n_sphere, rxyz_sphere, rcov_sphere, amp, om );
if ( (a = (double *) malloc(sizeof(double)*nid*nid)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);}
if ( (w = (double *) malloc(sizeof(double)*nid)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);}
for (i = 0; i < nid; i++)
for (j = 0; j< nid; j++)
a[i*nid + j] = om[j][i];
lda = nid;
lwork = -1;
/// for (i = 0; i< nid*nid; i++)
/// printf("a[%d]= %g\n", i, a[i]);
dsyev("V", "U", &nid, a, &lda, w, &wkopt, &lwork, &info);
lwork = (int)wkopt;
work = (double*) malloc(lwork*sizeof(double));
dsyev("V", "U", &nid, a, &lda, w, work, &lwork, &info);
if (info > 0 ) {
fprintf(stderr, "Error: DSYEV 1");
exit(1); }
if (w[0] < -1E-12) {
printf("w[0] = %g\n", w[0]);
fprintf(stderr, "Error: Negative w");
exit(1); }
for (i = 0; i < nid; i++)
pvec[i] = a[i + (nid-1)*nid];
if (flag <= 0 ) {
for (i = 0; i < nid; i++)
lfp[iat][i] = w[nid-1-i];
for (i = nid; i < nx; i++)
lfp[iat][i] = 0.0;
}
free(w);
free(a);
free(work);
if (flag >= 0 ){
/* contract */
nids = l*(ntyp+1);
for (i = 0; i < nids; i++) {
for (j = 0; j < nids; j++) {
omx[i][j] = 0.0;
omy[i][j] = 0.0;
}
}
for (i = 0; i < nid; i++)
for (j = 0; j < nid; j++)
omx[ind[i]][ind[j]] = omx[ind[i]][ind[j]] + pvec[i] * om[i][j] * pvec[j];
if ( (a = (double *) malloc(sizeof(double)*nids*nids)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);}
if ( (w = (double *) malloc(sizeof(double)*nids)) == NULL) {
fprintf(stderr, "Memory could not be allocated.");
exit(1);}
for (i = 0; i < nids; i++){
for (j = 0; j< nids; j++){
a[i*nids + j] = omx[j][i];
}
}
lda = nids;
lwork = -1;
dsyev("V", "U", &nids, a, &lda, w, &wkopt, &lwork, &info);
lwork = (int)wkopt;
work = (double*) malloc(lwork*sizeof(double));
dsyev("V", "U", &nids, a, &lda, w, work, &lwork, &info);
for (i = 0; i < nids; i++)
sfp[iat][i] = w[nids-1-i];
/*
printf("iat = %d\n", iat);
for (i = 0; i < nids; i++)
printf(" %e ", sfp[iat][i]);
printf("\n");
*/
free(a);
free(w);
}
free(work);
for (i = 0; i < n_sphere; i++)
free(om[i]);
free(om);
free(pvec);
}
printf("min %d, max %d\n", n_sphere_min, n_sphere_max);
}
void toast::lapack::syev ( char * JOBZ, char * UPLO, int * N, double * A, int * LDA, double * W, double * WORK, int * LWORK, int * INFO ) {
dsyev ( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, INFO );
return;
}
