source: src/grid/global_grid_partitioning.cpp@ 6f05224

/**
 * @file   global_grid_partitioning.hpp
 * @author Julian Iseringhausen <isering@ins.uni-bonn.de>
 * @date   Thu May 19 14:02:46 2011
 *
 * @brief  Class to store global grid partitioning.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cassert>

#include "grid/global_grid_partitioning.hpp"

using namespace VMG;

GlobalGridPartitioning::GlobalGridPartitioning(Index pos, Index procs, Index size, int points_min)
{
  Index i;
  Index index_beg, index_end;
  Index local_size;

  const Index active_procs = size / points_min;
  const Index size_per_proc = size / active_procs;
  const Index remainder = size % active_procs;

  for (i.X() = 0; i.X() < active_procs.X(); ++i.X())
    for (i.Y() = 0; i.Y() < active_procs.Y(); ++i.Y())
      for (i.Z() = 0; i.Z() < active_procs.Z(); ++i.Z()) {

        local_size = size_per_proc;

        for (int j=0; j<3; ++j)
          if (pos[j] < remainder[j])
            ++(local_size[j]);

        index_beg = i * local_size;

        for (int j=0; j<3; ++j)
          if (i[j] >= remainder[j])
            index_beg[j] += remainder[j];

        index_end = index_beg + local_size;

        begin.insert(std::make_pair(i, index_beg));
        end.insert(std::make_pair(i, index_end));

      }

}

const Index& GlobalGridPartitioning::GlobalBegin(const Index& pos) const
{
  std::map<Index, Index>::const_iterator iter = begin.find(pos);

  assert(iter != begin.end());

  return iter->second;
}

const Index& GlobalGridPartitioning::GlobalEnd(const Index& pos) const
{
  std::map<Index, Index>::const_iterator iter = end.find(pos);

  assert(iter != end.end());

  return iter->second;
}