Coarsen_Operator_Uniform.tpp

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#ifndef Coarsen_Operator_Uniform_TPP_H
#define Coarsen_Operator_Uniform_TPP_H
 
#include <Domaine_IJK.h>
#include <Perf_counters.h>
 
template<typename _TYPE_>
void Coarsen_Operator_Uniform::initialize_grid_data_(const Grid_Level_Data_template<_TYPE_>& fine,
                                                     Grid_Level_Data_template<_TYPE_>& coarse,
                                                     int additional_k_layers)
{
  const Domaine_IJK& src_grid_geom = fine.get_domaine();
  VECT(ArrOfDouble) coarse_delta(3);
  ArrOfInt nlocal(3);
 
  for (int dir = 0; dir < 3; dir++)
    {
      const int coarsen_factor = coarsen_factors_[dir];
      const ArrOfDouble& fine_delta = src_grid_geom.get_delta(dir);
 
      const int src_n = fine_delta.size_array();
      if (src_n % coarsen_factor != 0)
        {
          Cerr << "Coarsen_Operator_Uniform::initialize_grid_data: source grid has " << src_n
               << " elements in direction " << dir
               << " and cannot be refined by factor " << coarsen_factor << finl;
          Process::exit();
        }
      nlocal[dir] = fine.get_rho().nb_elem_local(dir);
      if (nlocal[dir] % coarsen_factor != 0)
        {
          Cerr << "Coarsen_Operator_Uniform::initialize_grid_data: local source grid processor has " << nlocal[dir]
               << " elements in direction " << dir
               << " and cannot be refined by factor " << coarsen_factor << finl;
          Process::exit();
        }
      nlocal[dir] /= coarsen_factor;
      const int n = src_n / coarsen_factor;
      ArrOfDouble& delta = coarse_delta[dir];
      delta.resize_array(n);
 
      int src_index = 0;
      delta.resize_array(n);
      for (int dest_index = 0; dest_index < n; dest_index++)
        {
          double d = 0;
          for (int j = 0; j < coarsen_factor; j++)
            {
              d += fine_delta[src_index];
              src_index++;
            }
          delta[dest_index] = d;
        }
    }
 
  Domaine_IJK grid_geom;
  grid_geom.initialize_origin_deltas(src_grid_geom.get_origin(0),
                                     src_grid_geom.get_origin(1),
                                     src_grid_geom.get_origin(2),
                                     coarse_delta[0],
                                     coarse_delta[1],
                                     coarse_delta[2],
                                     src_grid_geom.get_periodic_flag(0),
                                     src_grid_geom.get_periodic_flag(1),
                                     src_grid_geom.get_periodic_flag(2));
 
  Domaine_IJK coarse_splitting;
  // Same processor mapping as fine mesh
  IntTab processor_mapping;
  fine.get_domaine().get_processor_mapping(processor_mapping);
  // Splitting is identical, divide ncells by the coarsening factor
  VECT(ArrOfInt) slice_sizes(3);
  for (int dir = 0; dir < 3; dir++)
    {
      fine.get_domaine().get_slice_size(dir, Domaine_IJK::ELEM, slice_sizes[dir]);
      const int n = slice_sizes[dir].size_array();
      for (int i = 0; i < n; i++)
        slice_sizes[dir][i] /= coarsen_factors_[dir];
    }
  coarse_splitting.initialize_mapping(grid_geom, slice_sizes[0], slice_sizes[1], slice_sizes[2],
                                      processor_mapping);
  const int ghost_domaine_size = fine.get_ghost_size();
  coarse.initialize(coarse_splitting, ghost_domaine_size, additional_k_layers);
}
 
template <typename _TYPE_, typename _TYPE_ARRAY_>
void Coarsen_Operator_Uniform::coarsen_(const IJK_Field_template<_TYPE_,_TYPE_ARRAY_>& fine,
                                        IJK_Field_template<_TYPE_,_TYPE_ARRAY_>& coarse,
                                        int compute_weighted_average) const
{
  statistics().create_custom_counter("multigrid: uniform coarsening",2,"IJK");
  statistics().begin_count("multigrid: uniform coarsening",statistics().get_last_opened_counter_level()+1);
  const int ni2 = coarse.ni();
  const int nj2 = coarse.nj();
  const int nk2 = coarse.nk();
 
  _TYPE_ coef = 1;
  if (compute_weighted_average)
    coef = (_TYPE_)(1. / (coarsen_factors_[0] * coarsen_factors_[1] * coarsen_factors_[2]));
 
  const int Kstart = 0;
  const int Kend = nk2;
  const int deltaK = 1;
  for (int K = Kstart; K != Kend; K += deltaK)
    {
      const int k = K*coarsen_factors_[2];
      for (int J = 0; J < nj2; J++)
        {
          const int j = J*coarsen_factors_[1];
          for (int I = 0; I < ni2; I++)
            {
              const int i = I*coarsen_factors_[0];
              _TYPE_ sum = 0.;
              for (int ii = 0; ii < coarsen_factors_[0]; ii++)
                for (int jj = 0; jj < coarsen_factors_[1]; jj++)
                  for (int kk = 0; kk < coarsen_factors_[2]; kk++)
                    sum += fine(i + ii, j + jj, k + kk);
              coarse(I,J,K) = sum * coef;
            }
        }
    }
 
  statistics().end_count("multigrid: uniform coarsening");
  return;
}
 
template <typename _TYPE_, typename _TYPE_ARRAY_>
void Coarsen_Operator_Uniform::interpolate_sub_shiftk_(const IJK_Field_template<_TYPE_, _TYPE_ARRAY_>& coarse,
                                                       IJK_Field_template<_TYPE_, _TYPE_ARRAY_>& fine,
                                                       const int kshift) const
{
  if (kshift == 1)
    {
      Cerr << "error Coarsen_Operator_Uniform: kshift=1 will not work" << finl;
      Process::exit();
    }
 
  statistics().create_custom_counter("multigrid: interpolate uniform",2,"IJK");
  statistics().begin_count("multigrid: interpolate uniform",statistics().get_last_opened_counter_level()+1);
 
  const int ni2 = coarse.ni();
  const int nj2 = coarse.nj();
  const int nk2 = coarse.nk();
 
  const int Kstart = kshift <= 0 ? 0 : nk2 - 1;
  const int Kend = kshift <= 0 ? nk2 : -1;
  const int deltaK = kshift <= 0 ? 1 : -1;
 
  for (int K = Kstart; K != Kend; K += deltaK)
    {
      const int k = K*coarsen_factors_[2];
      for (int J = 0; J < nj2; ++J)
        {
          const int j = J*coarsen_factors_[1];
          for (int I = 0; I < ni2; ++I)
            {
              const int i = I*coarsen_factors_[0];
              const _TYPE_ val = coarse(I, J, K);
              for (int ii = 0; ii < coarsen_factors_[0]; ++ii)
                for (int jj = 0; jj < coarsen_factors_[1]; ++jj)
                  for (int kk = 0; kk < coarsen_factors_[2]; ++kk)
                    fine.get_in_allocated_area(i + ii, j + jj, k + kk + kshift) = fine(i + ii, j + jj, k + kk) - val;
            }
        }
    }
 
  fine.shift_k_origin(kshift);
  statistics().end_count("multigrid: interpolate uniform");
  return;
}
 
#endif