void setKnownXi_ReduceSizeOfEQS(std::vector<IndexValue> &list_dirichlet_bc, MathLib::CRSMatrix<
double, INDEX_TYPE> &eqsA, double* org_eqsRHS, double* org_eqsX, double** eqsRHS,
double** eqsX, std::map<INDEX_TYPE, INDEX_TYPE> &map_solved_orgEqs)
{
const size_t n_org_rows = eqsA.getNRows();
std::vector<INDEX_TYPE> removed_rows(list_dirichlet_bc.size());
std::cout << "[BC] (transpose matrix) ... " << std::flush;
RunTimeTimer run_trans;
run_trans.start();
MathLib::CRSMatrix<double, INDEX_TYPE>* transpose_mat (eqsA.getTranspose());
run_trans.stop();
std::cout << run_trans.elapsed() << " s" << std::endl;
INDEX_TYPE const*const row_ptr (transpose_mat->getRowPtrArray());
INDEX_TYPE const*const col_idx (transpose_mat->getColIdxArray());
double const*const data (transpose_mat->getEntryArray());
for (size_t i = 0; i < list_dirichlet_bc.size(); i++) {
IndexValue &bc = list_dirichlet_bc.at(i);
const size_t id = bc.id;
const double val = bc.val;
removed_rows.at(i) = id;
//b_i -= A(i,k)*val, i!=k
// for (size_t j = 0; j < eqsA.getNCols(); j++)
// org_eqsRHS[j] -= eqsA.getValue(j, id) * val;
const INDEX_TYPE end(row_ptr[id+1]);
for (INDEX_TYPE k(row_ptr[id]); k<end; k++) {
const INDEX_TYPE j(col_idx[k]);
org_eqsRHS[j] -= data[j] * val;
}
//b_k = A_kk*val
org_eqsRHS[id] = val; //=eqsA(id, id)*val;
org_eqsX[id] = val; //=eqsA(id, id)*val;
}
delete transpose_mat;
//remove rows and columns
eqsA.eraseEntries(removed_rows.size(), &removed_rows[0]);
//remove X,RHS
(*eqsX) = new double[n_org_rows - removed_rows.size()];
(*eqsRHS) = new double[n_org_rows-removed_rows.size()];
size_t new_id = 0;
for (size_t i=0; i<n_org_rows; i++) {
if (std::find(removed_rows.begin(), removed_rows.end(), static_cast<unsigned>(i))!=removed_rows.end()) continue;
(*eqsRHS)[new_id] = org_eqsRHS[i];
(*eqsX)[new_id] = org_eqsX[i];
map_solved_orgEqs[new_id] = i;
new_id++;
}
}
