SquareMatrix SqMRO_LUBackSubstitution::operator()(RowVector &indx, RowVector &b) const {
SquareMatrix a(*m_thisMatrix);
int n, i, j, ip, ii = -1;
double sum;
n = a.getRows();
for (i = 0; i < n; i++) {
ip = (int)indx(i);
sum = b.element(ip);
b.element(ip) = b.element(i);
if (ii != -1) {
for (j = ii; j < i; j++) {
sum -= a.element(i,j) * b.element(j);
}
} else if (sum) {
ii = i;
}
b.element(i) = sum;
}
for (i = (n - 1); i >= 0; i--) {
sum = b.element(i);
for (j = (i + 1); j < n; j++) {
sum -= a.element(i,j) * b.element(j);
}
b.element(i) = sum / a.element(i,i);
}
return a;
}
void SpinAdapted::Wavefunction::CollectFrom (const RowVector& C)
{
int flatIndex = 0;
for (int lQ = 0; lQ < nrows (); ++lQ)
for (int rQ = 0; rQ < ncols (); ++rQ)
if (allowedQuantaMatrix (lQ, rQ))
for (int lQState = 0; lQState < operator_element(lQ, rQ).Nrows (); ++lQState)
for (int rQState = 0; rQState < operator_element(lQ, rQ).Ncols (); ++rQState)
{
operator_element(lQ, rQ).element (lQState, rQState) = C.element (flatIndex);
++flatIndex;
}
}
SquareMatrix SqMRO_LUDecomposition::operator()(RowVector &indx, double *d) const {
SquareMatrix a(*m_thisMatrix);
int n, i, imax, j, k;
double big, dum, sum, temp;
RowVector vv(a.getRows());
n = a.getRows();
// No row interchanges yet
*d = 1.0;
// Loop over rows to get implicit scaling information
for (i = 0; i < n; i++) {
big = 0.0;
for (j = 0; j < n; j++) {
temp = fabs(a.element(i,j));
if (temp > big) {
big = temp;
}
}
if (big == 0.0) {
error("SquareMatrixAlias::luDecomp : MatrixAlias is rank defficient\n\n");
return a;
}
vv(i) = 1 / big;
}
// Loop over columns (Crout's method)
for (j = 0; j < n; j++) {
for (i = 0; i < j; i++) {
sum = a.element(i,j);
for (k = 0; k < i; k++) {
sum -= a.element(i,k) * a.element(k,j);
}
a.element(i,j) = sum;
}
big = 0;
for (i = j; i < n; i++) {
sum = a.element(i,j);
for (k = 0; k < j; k++) {
sum -= a.element(i,k) * a.element(k,j);
}
a.element(i,j) = sum;
dum = vv(i) * fabs(sum);
if (dum >= big) {
big = dum;
imax = i;
}
}
if (j != imax) {
for (k = 0; k < n; k++) {
dum = a.element(imax,k);
a.element(imax,k) = a.element(j,k);
a.element(j,k) = dum;
}
*d = -(*d);
vv(imax) = vv(j);
}
indx.element(j) = imax;
// Singularity may arise as aresult of rounding errors
// Substitute in small values for zeros
if (a.element(j,j) == 0) {
error("SquareMatrixAlias::luDecomp : MatrixAlias is rank defficient\n\n");
a.element(j,j) = 1e-100;
}
if (j != n) {
dum = 1 / a.element(j,j);
for (i = j+1; i < n; i++) {
a.element(i,j) *= dum;
}
}
}
return a;
}
