lbs_DSA_preconditioner.cc

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#include "lbs_shell_operations.h"
 
#include "A_LBSSolver/lbs_solver.h"
#include "A_LBSSolver/Acceleration/diffusion_mip.h"
#include "LinearBoltzmannSolvers/A_LBSSolver/IterativeMethods/wgs_context.h"
 
//###################################################################
/**Applies WGDSA or TGDSA to the given input vector.*/
int lbs::WGDSA_TGDSA_PreConditionerMult(PC pc, Vec phi_input, Vec pc_output)
{
  void* context;
  PCShellGetContext(pc,&context);
 
  auto gs_context_ptr = (lbs::WGSContext<Mat,Vec,KSP>*)(context);
 
  //Shorten some names
  lbs::LBSSolver& lbs_solver = gs_context_ptr->lbs_solver_;
  LBSGroupset& groupset  = gs_context_ptr->groupset_;
 
  //============================================= Copy PETSc vector to STL
  auto& phi_new_local = gs_context_ptr->lbs_solver_.PhiNewLocal();
  lbs_solver.SetPrimarySTLvectorFromGSPETScVec(groupset, phi_input,
                                               PhiSTLOption::PHI_NEW);
 
  //============================================= Apply WGDSA
  if (groupset.apply_wgdsa_)
  {
    std::vector<double> delta_phi_local;
    lbs_solver.AssembleWGDSADeltaPhiVector(groupset,phi_new_local, //From
                                           delta_phi_local);       //To
 
    groupset.wgdsa_solver_->Assemble_b(delta_phi_local);
    groupset.wgdsa_solver_->Solve(delta_phi_local);
 
    lbs_solver.DisAssembleWGDSADeltaPhiVector(groupset, delta_phi_local, //From
                                              phi_new_local);            //To
  }
  //============================================= Apply TGDSA
  if (groupset.apply_tgdsa_)
  {
    std::vector<double> delta_phi_local;
    lbs_solver.AssembleTGDSADeltaPhiVector(groupset, phi_new_local, //From
                                           delta_phi_local);        //To
 
    groupset.tgdsa_solver_->Assemble_b(delta_phi_local);
    groupset.tgdsa_solver_->Solve(delta_phi_local);
 
    lbs_solver.DisAssembleTGDSADeltaPhiVector(groupset, delta_phi_local, //From
                                              phi_new_local);            //To
  }
 
  //============================================= Copy STL vector to PETSc Vec
  lbs_solver.SetGSPETScVecFromPrimarySTLvector(groupset, pc_output,
                                               PhiSTLOption::PHI_NEW);
 
  return 0;
}
 
//###################################################################
/**Applies WGDSA or TGDSA to the given input vector.*/
int lbs::WGDSA_TGDSA_PreConditionerMult2(
  lbs::WGSContext<Mat,Vec,KSP>& gs_context_ptr,
  Vec phi_input, Vec pc_output)
{
  //Shorten some names
  lbs::LBSSolver& lbs_solver = gs_context_ptr.lbs_solver_;
  LBSGroupset& groupset  = gs_context_ptr.groupset_;
 
  //============================================= Copy PETSc vector to STL
  auto& phi_new_local = gs_context_ptr.lbs_solver_.PhiNewLocal();
  lbs_solver.SetPrimarySTLvectorFromGSPETScVec(groupset, phi_input,
                                               PhiSTLOption::PHI_NEW);
 
  //============================================= Apply WGDSA
  if (groupset.apply_wgdsa_)
  {
    std::vector<double> delta_phi_local;
    lbs_solver.AssembleWGDSADeltaPhiVector(groupset,phi_new_local, //From
                                           delta_phi_local);       //To
 
    groupset.wgdsa_solver_->Assemble_b(delta_phi_local);
    groupset.wgdsa_solver_->Solve(delta_phi_local);
 
    lbs_solver.DisAssembleWGDSADeltaPhiVector(groupset, delta_phi_local, //From
                                              phi_new_local);            //To
  }
  //============================================= Apply TGDSA
  if (groupset.apply_tgdsa_)
  {
    std::vector<double> delta_phi_local;
    lbs_solver.AssembleTGDSADeltaPhiVector(groupset, phi_new_local, //From
                                           delta_phi_local);        //To
 
    groupset.tgdsa_solver_->Assemble_b(delta_phi_local);
    groupset.tgdsa_solver_->Solve(delta_phi_local);
 
    lbs_solver.DisAssembleTGDSADeltaPhiVector(groupset, delta_phi_local, //From
                                              phi_new_local);            //To
  }
 
  //============================================= Copy STL vector to PETSc Vec
  lbs_solver.SetGSPETScVecFromPrimarySTLvector(groupset, pc_output,
                                               PhiSTLOption::PHI_NEW);
 
  return 0;
}