void Print(const DiagonalMatrix& X)
{
++PCN;
cout << "\nMatrix type: " << X.Type().Value() << " (";
cout << X.Nrows() << ", ";
cout << X.Ncols() << ")\n\n";
if (X.IsZero()) { cout << "All elements are zero\n" << flush; return; }
int nr=X.Nrows(); int nc=X.Ncols();
for (int i=1; i<=nr; i++)
{
for (int j=1; j<i; j++) cout << "\t";
if (i<=nc) cout << X(i,i) << "\t";
cout << "\n";
}
cout << flush; ++PCZ;
}
void SpinAdapted::Linear::block_davidson(vector<Wavefunction>& b, DiagonalMatrix& h_diag, double normtol, const bool &warmUp, Davidson_functor& h_multiply, bool& useprecond, int currentRoot, std::vector<Wavefunction> &lowerStates)
{
pout.precision (12);
#ifndef SERIAL
mpi::communicator world;
#endif
int iter = 0;
double levelshift = 0.0;
int nroots = b.size();
//normalise all the guess roots
if(mpigetrank() == 0) {
for(int i=0; i<nroots; ++i)
{
for(int j=0; j<i; ++j)
{
double overlap = DotProduct(b[j], b[i]);
ScaleAdd(-overlap, b[j], b[i]);
}
Normalise(b[i]);
}
//if we are doing state specific, lowerstates has lower energy states
if (lowerStates.size() != 0) {
for (int i=0; i<lowerStates.size(); i++) {
double overlap = DotProduct(b[0], lowerStates[i]);
ScaleAdd(-overlap/DotProduct(lowerStates[i], lowerStates[i]), lowerStates[i], b[0]);
}
Normalise(b[0]);
}
}
vector<Wavefunction> sigma;
int converged_roots = 0;
int maxiter = h_diag.Ncols() - lowerStates.size();
while(true)
{
if (dmrginp.outputlevel() > 0)
pout << "\t\t\t Davidson Iteration :: " << iter << endl;
++iter;
dmrginp.hmultiply -> start();
int sigmasize, bsize;
if (mpigetrank() == 0) {
sigmasize = sigma.size();
bsize = b.size();
}
#ifndef SERIAL
mpi::broadcast(world, sigmasize, 0);
mpi::broadcast(world, bsize, 0);
#endif
//multiply all guess vectors with hamiltonian c = Hv
for(int i=sigmasize; i<bsize; ++i) {
Wavefunction sigmai, bi;
Wavefunction* sigmaptr=&sigmai, *bptr = &bi;
if (mpigetrank() == 0) {
sigma.push_back(b[i]);
sigma[i].Clear();
sigmaptr = &sigma[i];
bptr = &b[i];
}
#ifndef SERIAL
mpi::broadcast(world, *bptr, 0);
#endif
if (mpigetrank() != 0) {
sigmai = bi;
sigmai.Clear();
}
h_multiply(*bptr, *sigmaptr);
//if (mpigetrank() == 0) {
// cout << *bptr << endl;
// cout << *sigmaptr << endl;
//}
}
dmrginp.hmultiply -> stop();
Wavefunction r;
DiagonalMatrix subspace_eigenvalues;
if (mpigetrank() == 0) {
Matrix subspace_h(b.size(), b.size());
for (int i = 0; i < b.size(); ++i)
for (int j = 0; j <= i; ++j) {
subspace_h.element(i, j) = DotProduct(b[i], sigma[j]);
subspace_h.element(j, i) = subspace_h.element(i, j);
}
Matrix alpha;
diagonalise(subspace_h, subspace_eigenvalues, alpha);
if (dmrginp.outputlevel() > 0) {
for (int i = 1; i <= subspace_eigenvalues.Ncols (); ++i)
pout << "\t\t\t " << i << " :: " << subspace_eigenvalues(i,i)+dmrginp.get_coreenergy() << endl;
}
//now calculate the ritz vectors which are approximate eigenvectors
vector<Wavefunction> btmp = b;
vector<Wavefunction> sigmatmp = sigma;
for (int i = 0; i < b.size(); ++i)
{
Scale(alpha.element(i, i), b[i]);
Scale(alpha.element(i, i), sigma[i]);
}
for (int i = 0; i < b.size(); ++i)
for (int j = 0; j < b.size(); ++j)
{
if (i != j)
{
ScaleAdd(alpha.element(i, j), btmp[i], b[j]);
ScaleAdd(alpha.element(i, j), sigmatmp[i], sigma[j]);
}
}
// build residual
for (int i=0; i<converged_roots; i++) {
r = sigma[i];
ScaleAdd(-subspace_eigenvalues(i+1), b[i], r);
double rnorm = DotProduct(r,r);
if (rnorm > normtol) {
converged_roots = i;
if (dmrginp.outputlevel() > 0)
pout << "\t\t\t going back to converged root "<<i<<" "<<rnorm<<" > "<<normtol<<endl;
continue;
}
}
r = sigma[converged_roots];
ScaleAdd(-subspace_eigenvalues(converged_roots+1), b[converged_roots], r);
if (lowerStates.size() != 0) {
for (int i=0; i<lowerStates.size(); i++) {
double overlap = DotProduct(r, lowerStates[i]);
ScaleAdd(-overlap/DotProduct(lowerStates[i], lowerStates[i]), lowerStates[i], r);
//ScaleAdd(-overlap, lowerStates[i], r);
}
}
}
double rnorm;
if (mpigetrank() == 0)
rnorm = DotProduct(r,r);
#ifndef SERIAL
mpi::broadcast(world, converged_roots, 0);
mpi::broadcast(world, rnorm, 0);
#endif
if (useprecond && mpigetrank() == 0)
olsenPrecondition(r, b[converged_roots], subspace_eigenvalues(converged_roots+1), h_diag, levelshift);
if (dmrginp.outputlevel() > 0)
pout << "\t \t \t residual :: " << rnorm << endl;
if (rnorm < normtol)
{
if (dmrginp.outputlevel() > 0)
pout << "\t\t\t Converged root " << converged_roots << endl;
++converged_roots;
if (converged_roots == nroots)
{
if (mpigetrank() == 0) {
for (int i = 0; i < min((int)(b.size()), h_diag.Ncols()); ++i)
h_diag.element(i) = subspace_eigenvalues.element(i);
}
break;
}
}
else if (mpigetrank() == 0)
{
if(b.size() >= dmrginp.deflation_max_size())
{
if (dmrginp.outputlevel() > 0)
pout << "\t\t\t Deflating block Davidson...\n";
b.resize(dmrginp.deflation_min_size());
sigma.resize(dmrginp.deflation_min_size());
}
for (int j = 0; j < b.size(); ++j)
{
//Normalize
double normalization = DotProduct(r, r);
Scale(1./sqrt(normalization), r);
double overlap = DotProduct(r, b[j]);
ScaleAdd(-overlap, b[j], r);
}
//if we are doing state specific, lowerstates has lower energy states
if (lowerStates.size() != 0) {
for (int i=0; i<lowerStates.size(); i++) {
double overlap = DotProduct(r, lowerStates[i]);
ScaleAdd(-overlap/DotProduct(lowerStates[i], lowerStates[i]), lowerStates[i], r);
//ScaleAdd(-overlap, lowerStates[i], r);
}
}
//double tau2 = DotProduct(r,r);
Normalise(r);
b.push_back(r);
}
}
}
