Zoltan2_TaskMapping.hpp

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#ifndef _ZOLTAN2_COORD_PARTITIONMAPPING_HPP_
#define _ZOLTAN2_COORD_PARTITIONMAPPING_HPP_

#include <fstream>
#include <ctime>
#include <vector>
#include <set>
#include <tuple>

#include "Zoltan2_AlgMultiJagged.hpp"
#include "Teuchos_ArrayViewDecl.hpp"
#include "Zoltan2_PartitionMapping.hpp"
#include "Zoltan2_MachineRepresentation.hpp"
#include "Teuchos_ReductionOp.hpp"

#include "Zoltan2_MappingSolution.hpp"

#include "Zoltan2_GraphModel.hpp"
#include <zoltan_dd.h>
#include <Zoltan2_TPLTraits.hpp>

#include "Teuchos_Comm.hpp"
#ifdef HAVE_ZOLTAN2_MPI
#include "Teuchos_DefaultMpiComm.hpp"
#endif // HAVE_ZOLTAN2_MPI
#include <Teuchos_DefaultSerialComm.hpp>

//#define gnuPlot
#include "Zoltan2_XpetraMultiVectorAdapter.hpp"

namespace Teuchos{

template <typename Ordinal, typename T>
class Zoltan2_ReduceBestMapping  : public ValueTypeReductionOp<Ordinal,T>
{
private:
  T _EPSILON;

public:
  Zoltan2_ReduceBestMapping ():_EPSILON (std::numeric_limits<T>::epsilon()){}

  void reduce( const Ordinal count, const T inBuffer[], T inoutBuffer[]) const
  {

    for (Ordinal i=0; i < count; i++){
      if (inBuffer[0] - inoutBuffer[0] < -_EPSILON){
        inoutBuffer[0] = inBuffer[0];
        inoutBuffer[1] = inBuffer[1];
      } else if(inBuffer[0] - inoutBuffer[0] < _EPSILON &&
          inBuffer[1] - inoutBuffer[1] < _EPSILON){
        inoutBuffer[0] = inBuffer[0];
        inoutBuffer[1] = inBuffer[1];
      }
    }
  }
};
} // namespace Teuchos


namespace Zoltan2{

template <typename it>
inline it z2Fact(it x) {
  return (x == 1 ? x : x * z2Fact<it>(x - 1));
}

template <typename gno_t, typename part_t>
class GNO_LNO_PAIR{
public:
  gno_t gno;
  part_t part;
};

//returns the ith permutation indices.
template <typename IT>
void ithPermutation(const IT n, IT i, IT *perm)
{
  IT j, k = 0;
  IT *fact = new IT[n];


  // compute factorial numbers
  fact[k] = 1;
  while (++k < n)
    fact[k] = fact[k - 1] * k;

  // compute factorial code
  for (k = 0; k < n; ++k)
  {
    perm[k] = i / fact[n - 1 - k];
    i = i % fact[n - 1 - k];
  }

  // readjust values to obtain the permutation
  // start from the end and check if preceding values are lower
  for (k = n - 1; k > 0; --k)
    for (j = k - 1; j >= 0; --j)
      if (perm[j] <= perm[k])
        perm[k]++;

  delete [] fact;
}

template <typename part_t>
void getGridCommunicationGraph(part_t taskCount, part_t *&task_comm_xadj, part_t *&task_comm_adj, std::vector <int> grid_dims){
  int dim = grid_dims.size();
  int neighborCount = 2 * dim;
  task_comm_xadj = allocMemory<part_t>(taskCount+1);
  task_comm_adj = allocMemory<part_t>(taskCount * neighborCount);

  part_t neighBorIndex = 0;
  task_comm_xadj[0] = 0;
  for (part_t i = 0; i < taskCount; ++i){
    part_t prevDimMul = 1;
    for (int j = 0; j < dim; ++j){
      part_t lNeighbor = i - prevDimMul;
      part_t rNeighbor = i + prevDimMul;
      prevDimMul *= grid_dims[j];
      if (lNeighbor >= 0 &&  lNeighbor/ prevDimMul == i / prevDimMul && lNeighbor < taskCount){
        task_comm_adj[neighBorIndex++] = lNeighbor;
      }
      if (rNeighbor >= 0 && rNeighbor/ prevDimMul == i / prevDimMul && rNeighbor < taskCount){
        task_comm_adj[neighBorIndex++] = rNeighbor;
      }
    }
    task_comm_xadj[i+1] = neighBorIndex;
  }

}
//returns the center of the parts.
template <typename Adapter, typename scalar_t, typename part_t>
void getSolutionCenterCoordinates(
    const Environment *envConst,
    const Teuchos::Comm<int> *comm,
    const Zoltan2::CoordinateModel<typename Adapter::base_adapter_t> *coords,
    //const Zoltan2::PartitioningSolution<Adapter> *soln_,
    const part_t *parts,
    int coordDim,
    part_t ntasks,
    scalar_t **partCenters){

  typedef typename Adapter::lno_t lno_t;
  typedef typename Adapter::gno_t gno_t;

  typedef StridedData<lno_t, scalar_t> input_t;
  ArrayView<const gno_t> gnos;
  ArrayView<input_t>     xyz;
  ArrayView<input_t>     wgts;
  coords->getCoordinates(gnos, xyz, wgts);

  //local and global num coordinates.
  lno_t numLocalCoords = coords->getLocalNumCoordinates();
  //gno_t numGlobalCoords = coords->getGlobalNumCoordinates();



  //local number of points in each part.
  gno_t *point_counts = allocMemory<gno_t>(ntasks);
  memset(point_counts, 0, sizeof(gno_t) * ntasks);

  //global number of points in each part.
  gno_t *global_point_counts = allocMemory<gno_t>(ntasks);


  scalar_t **multiJagged_coordinates = allocMemory<scalar_t *>(coordDim);

  for (int dim=0; dim < coordDim; dim++){
    ArrayRCP<const scalar_t> ar;
    xyz[dim].getInputArray(ar);
    //multiJagged coordinate values assignment
    multiJagged_coordinates[dim] =  (scalar_t *)ar.getRawPtr();
    memset(partCenters[dim], 0, sizeof(scalar_t) * ntasks);
  }

  //get parts with parallel gnos.
  //const part_t *parts = soln_->getPartListView();
  /*
    for (lno_t i=0; i < numLocalCoords; i++){
  cout << "me:" << comm->getRank() << " gno:" << soln_gnos[i] << " tmp.part :" << parts[i]<< endl;
    }
   */


  envConst->timerStart(MACRO_TIMERS, "Mapping - Center Calculation");


  for (lno_t i=0; i < numLocalCoords; i++){
    part_t p = parts[i];
    //add up all coordinates in each part.
    for(int j = 0; j < coordDim; ++j){
      scalar_t c = multiJagged_coordinates[j][i];
      partCenters[j][p] += c;
    }
    ++point_counts[p];
  }

  //get global number of points in each part.
  reduceAll<int, gno_t>(*comm, Teuchos::REDUCE_SUM,
      ntasks, point_counts, global_point_counts
  );

  for(int j = 0; j < coordDim; ++j){
    for (part_t i=0; i < ntasks; ++i){
      partCenters[j][i] /= global_point_counts[i];
    }
  }

  scalar_t *tmpCoords = allocMemory<scalar_t>(ntasks);
  for(int j = 0; j < coordDim; ++j){
    reduceAll<int, scalar_t>(*comm, Teuchos::REDUCE_SUM,
        ntasks, partCenters[j], tmpCoords
    );

    scalar_t *tmp = partCenters[j];
    partCenters[j] = tmpCoords;
    tmpCoords = tmp;
  }
  envConst->timerStop(MACRO_TIMERS, "Mapping - Center Calculation");

  freeArray<gno_t> (point_counts);
  freeArray<gno_t> (global_point_counts);

  freeArray<scalar_t> (tmpCoords);
  freeArray<scalar_t *>(multiJagged_coordinates);
}

//returns the coarsend part graph.
template <typename Adapter, typename scalar_t, typename part_t>
void getCoarsenedPartGraph(
    const Environment *envConst,
    const Teuchos::Comm<int> *comm,
    const Zoltan2::GraphModel<typename Adapter::base_adapter_t> *graph,
    //const Zoltan2::PartitioningSolution<Adapter> *soln_,
    part_t np,
    const part_t *parts,
    ArrayRCP<part_t> &g_part_xadj,
    ArrayRCP<part_t> &g_part_adj,
    ArrayRCP<scalar_t> &g_part_ew
    ){

  typedef typename Adapter::lno_t t_lno_t;
  typedef typename Adapter::gno_t t_gno_t;
  typedef typename Adapter::scalar_t t_scalar_t;
  typedef typename Zoltan2::GraphModel<typename Adapter::base_adapter_t>::input_t t_input_t;

  //int numRanks = comm->getSize();
  //int myRank = comm->getRank();

  //get parts with parallel gnos.
  /*
  const part_t *parts = soln_->getPartListView();

  part_t np = soln_->getActualGlobalNumberOfParts();
  if (part_t (soln_->getTargetGlobalNumberOfParts()) > np){
    np = soln_->getTargetGlobalNumberOfParts();
  }
  */


  t_lno_t localNumVertices = graph->getLocalNumVertices();
  t_lno_t localNumEdges = graph->getLocalNumEdges();

  //get the vertex global ids, and weights
  ArrayView<const t_gno_t> Ids;
  ArrayView<t_input_t> v_wghts;
  graph->getVertexList(Ids, v_wghts);

  //get the edge ids, and weights
  ArrayView<const t_gno_t> edgeIds;
  ArrayView<const t_lno_t> offsets;
  ArrayView<t_input_t> e_wgts;
  graph->getEdgeList(edgeIds, offsets, e_wgts);


  std::vector <t_scalar_t> edge_weights;
  int numWeightPerEdge = graph->getNumWeightsPerEdge();

  if (numWeightPerEdge > 0){
    edge_weights =  std::vector <t_scalar_t> (localNumEdges);
    for (t_lno_t i = 0; i < localNumEdges; ++i){
      edge_weights[i] = e_wgts[0][i];
    }
  }

  //create a zoltan dictionary to get the parts of the vertices
  //at the other end of edges
  std::vector <part_t> e_parts (localNumEdges);
#ifdef HAVE_ZOLTAN2_MPI
  if (comm->getSize() > 1)
  {
    Zoltan_DD_Struct *dd = NULL;

    MPI_Comm mpicomm = Teuchos::getRawMpiComm(*comm);
    int size_gnot = Zoltan2::TPL_Traits<ZOLTAN_ID_PTR, t_gno_t>::NUM_ID;

    int debug_level = 0;
    Zoltan_DD_Create(&dd, mpicomm,
        size_gnot, 0,
        sizeof(part_t), localNumVertices, debug_level);

    ZOLTAN_ID_PTR ddnotneeded = NULL;  // Local IDs not needed
    Zoltan_DD_Update(
        dd,
        (ZOLTAN_ID_PTR) Ids.getRawPtr(),
        ddnotneeded,
        (char *) parts,
        NULL,
        int(localNumVertices));

    Zoltan_DD_Find(
        dd,
        (ZOLTAN_ID_PTR) edgeIds.getRawPtr(),
        ddnotneeded,
        (char *)&(e_parts[0]),
        NULL,
        localNumEdges,
        NULL
        );
    Zoltan_DD_Destroy(&dd);
  } else
#endif
  {

    /*
    std::cout << "localNumVertices:" << localNumVertices
              << " np:" << np
              << " globalNumVertices:" << graph->getGlobalNumVertices()
              << " localNumEdges:" << localNumEdges << std::endl;
              */

    for (t_lno_t i = 0; i < localNumEdges; ++i){
      t_gno_t ei = edgeIds[i];
      part_t p = parts[ei];
      e_parts[i] = p;
    }

    //get the vertices in each part in my part.
    std::vector <t_lno_t> part_begins(np, -1);
    std::vector <t_lno_t> part_nexts(localNumVertices, -1);

    //cluster vertices according to their parts.
    //create local part graph.
    for (t_lno_t i = 0; i < localNumVertices; ++i){
      part_t ap = parts[i];
      part_nexts[i] = part_begins[ap];
      part_begins[ap] = i;
    }


    g_part_xadj = ArrayRCP<part_t> (np + 1);
    g_part_adj = ArrayRCP<part_t> (localNumEdges);
    g_part_ew = ArrayRCP<t_scalar_t> (localNumEdges);
    part_t nindex = 0;
    g_part_xadj[0] = 0;
    std::vector <part_t> part_neighbors (np);
    std::vector <t_scalar_t> part_neighbor_weights(np, 0);
    std::vector <t_scalar_t> part_neighbor_weights_ordered(np);

    //coarsen for all vertices in my part in order with parts.
    for (t_lno_t i = 0; i < np; ++i){
      part_t num_neighbor_parts = 0;
      t_lno_t v = part_begins[i];
      //get part i, and first vertex in this part v.
      while (v != -1){
        //now get the neightbors of v.
        for (t_lno_t j = offsets[v]; j < offsets[v+1]; ++j){
          //get the part of the second vertex.
          part_t ep = e_parts[j];

          t_scalar_t ew = 1;
          if (numWeightPerEdge > 0){
            ew = edge_weights[j];
          }
          //std::cout << "part:" << i << " v:" << v << " part2:" << ep  << " v2:" << edgeIds[j] << " w:" << ew << std::endl;
          //add it to my local part neighbors for part i.
          if (part_neighbor_weights[ep] < 0.00001){
            part_neighbors[num_neighbor_parts++] = ep;
          }
          part_neighbor_weights[ep] += ew;
        }
        v = part_nexts[v];
      }


      //now get the part list.
      for (t_lno_t j = 0; j < num_neighbor_parts; ++j){
        part_t neighbor_part = part_neighbors[j];
        g_part_adj[nindex] = neighbor_part;
        g_part_ew[nindex++] = part_neighbor_weights[neighbor_part];
        part_neighbor_weights[neighbor_part] = 0;
      }
      g_part_xadj[i + 1] = nindex;
    }
    return;
  }

  RCP<const Teuchos::Comm<int> > tcomm = rcpFromRef(*comm);
  typedef Tpetra::Map<>::node_type t_node_t;
  typedef Tpetra::Map<part_t, part_t, t_node_t> t_map_t;
  Teuchos::RCP<const t_map_t> map = Teuchos::rcp (new t_map_t (np, 0, tcomm));
  typedef Tpetra::CrsMatrix<t_scalar_t, part_t, part_t, t_node_t> tcrsMatrix_t;
  Teuchos::RCP<tcrsMatrix_t> tMatrix(new tcrsMatrix_t (map, 0));



  envConst->timerStart(MACRO_TIMERS, "GRAPHCREATE Coarsen");
  {
    //get the vertices in each part in my part.
    std::vector <t_lno_t> part_begins(np, -1);
    std::vector <t_lno_t> part_nexts(localNumVertices, -1);

    //cluster vertices according to their parts.
    //create local part graph.
    for (t_lno_t i = 0; i < localNumVertices; ++i){
      part_t ap = parts[i];
      part_nexts[i] = part_begins[ap];
      part_begins[ap] = i;
    }

    std::vector <part_t> part_neighbors (np);
    std::vector <t_scalar_t> part_neighbor_weights(np, 0);
    std::vector <t_scalar_t> part_neighbor_weights_ordered(np);

    //coarsen for all vertices in my part in order with parts.
    for (t_lno_t i = 0; i < np; ++i){
      part_t num_neighbor_parts = 0;
      t_lno_t v = part_begins[i];
      //get part i, and first vertex in this part v.
      while (v != -1){
        //now get the neightbors of v.
        for (t_lno_t j = offsets[v]; j < offsets[v+1]; ++j){
          //get the part of the second vertex.
          part_t ep = e_parts[j];

          t_scalar_t ew = 1;
          if (numWeightPerEdge > 0){
            ew = edge_weights[j];
          }
          //add it to my local part neighbors for part i.
          if (part_neighbor_weights[ep] < 0.00001){
            part_neighbors[num_neighbor_parts++] = ep;
          }
          part_neighbor_weights[ep] += ew;
        }
        v = part_nexts[v];
      }

      //now get the part list.
      for (t_lno_t j = 0; j < num_neighbor_parts; ++j){
        part_t neighbor_part = part_neighbors[j];
        part_neighbor_weights_ordered[j] = part_neighbor_weights[neighbor_part];
        part_neighbor_weights[neighbor_part] = 0;
      }

      //insert it to tpetra crsmatrix.
      if (num_neighbor_parts > 0){
        Teuchos::ArrayView<const part_t> destinations(
            &(part_neighbors[0]), num_neighbor_parts);
        Teuchos::ArrayView<const t_scalar_t>
        vals(&(part_neighbor_weights_ordered[0]), num_neighbor_parts);
        tMatrix->insertGlobalValues (i,destinations, vals);
      }
    }
  }
  envConst->timerStop(MACRO_TIMERS, "GRAPHCREATE Coarsen");
  envConst->timerStart(MACRO_TIMERS, "GRAPHCREATE fillComplete");
  tMatrix->fillComplete ();
  envConst->timerStop(MACRO_TIMERS, "GRAPHCREATE fillComplete");


  std::vector <part_t> part_indices(np);

  for (part_t i = 0; i < np; ++i) part_indices[i] = i;

  Teuchos::ArrayView<const part_t>
    global_ids( &(part_indices[0]), np);

  //create a map where all processors own all rows.
  //so that we do a gatherAll for crsMatrix.
  Teuchos::RCP<const t_map_t> gatherRowMap(new t_map_t (
      Teuchos::OrdinalTraits<Tpetra::global_size_t>::invalid(), global_ids, 0, tcomm));

  envConst->timerStart(MACRO_TIMERS, "GRAPHCREATE Import");
  //create the importer for gatherAll
  Teuchos::RCP<tcrsMatrix_t> A_gather =
      Teuchos::rcp (new tcrsMatrix_t (gatherRowMap, 0));
  typedef Tpetra::Import<typename t_map_t::local_ordinal_type,
                         typename t_map_t::global_ordinal_type,
                         typename t_map_t::node_type> import_type;
  import_type import (map, gatherRowMap);
  A_gather->doImport (*tMatrix, import, Tpetra::INSERT);
  A_gather->fillComplete ();
  envConst->timerStop(MACRO_TIMERS, "GRAPHCREATE Import");

  //create the output part arrays.
  //all processors owns whole copy.
  g_part_xadj = ArrayRCP<part_t> (np + 1);
  g_part_adj = ArrayRCP<part_t> (A_gather->getNodeNumEntries ());
  g_part_ew = ArrayRCP<t_scalar_t> (A_gather->getNodeNumEntries ());

  part_t *taskidx = g_part_xadj.getRawPtr();
  part_t *taskadj = g_part_adj.getRawPtr();
  t_scalar_t *taskadjwgt = g_part_ew.getRawPtr();

  taskidx[0] = 0;

  envConst->timerStart(MACRO_TIMERS, "GRAPHCREATE Import Copy");
  for (part_t i = 0; i < np; i++) {
    part_t length = A_gather->getNumEntriesInLocalRow(i);  // Use Global to get same
    size_t nentries;
    taskidx[i+1] = taskidx[i] + length;
    //get the indices
    Teuchos::ArrayView<part_t> Indices(taskadj + taskidx[i], length);
    Teuchos::ArrayView<t_scalar_t> Values(taskadjwgt + taskidx[i], length);
    A_gather->getLocalRowCopy(i, Indices, Values, nentries);
  }
  envConst->timerStop(MACRO_TIMERS, "GRAPHCREATE Import Copy");
}


template <class IT, class WT>
class KmeansHeap{
  IT heapSize;
  IT *indices;
  WT *values;
  WT _EPSILON;


public:
  void setHeapsize(IT heapsize_){
    this->heapSize = heapsize_;
    this->indices = allocMemory<IT>(heapsize_ );
    this->values = allocMemory<WT>(heapsize_ );
    this->_EPSILON = std::numeric_limits<WT>::epsilon();
  }

  ~KmeansHeap(){
    freeArray<IT>(this->indices);
    freeArray<WT>(this->values);
  }


  void addPoint(IT index, WT distance){
    WT maxVal = this->values[0];
    //add only the distance is smaller than the maximum distance.
    //cout << "indeX:" << index << "distance:" <<distance << " maxVal:" << maxVal << endl;
    if (distance >= maxVal) return;
    else {
      this->values[0] = distance;
      this->indices[0] = index;
      this->push_down(0);
    }
  }

  //heap push down operation
  void push_down(IT index_on_heap){
    IT child_index1 = 2 * index_on_heap + 1;
    IT child_index2 = 2 * index_on_heap + 2;

    IT biggerIndex = -1;
    if(child_index1 < this->heapSize && child_index2 < this->heapSize){

      if (this->values[child_index1] < this->values[child_index2]){
        biggerIndex = child_index2;
      }
      else {
        biggerIndex = child_index1;
      }
    }
    else if(child_index1 < this->heapSize){
      biggerIndex = child_index1;

    }
    else if(child_index2 < this->heapSize){
      biggerIndex = child_index2;
    }
    if (biggerIndex >= 0 && this->values[biggerIndex] > this->values[index_on_heap]){
      WT tmpVal = this->values[biggerIndex];
      this->values[biggerIndex] = this->values[index_on_heap];
      this->values[index_on_heap] = tmpVal;

      IT tmpIndex = this->indices[biggerIndex];
      this->indices[biggerIndex] = this->indices[index_on_heap];
      this->indices[index_on_heap] = tmpIndex;
      this->push_down(biggerIndex);
    }
  }

  void initValues(){
    WT MAXVAL = std::numeric_limits<WT>::max();
    for(IT i = 0; i < this->heapSize; ++i){
      this->values[i] = MAXVAL;
      this->indices[i] = -1;
    }
  }

  //returns the total distance to center in the cluster.
  WT getTotalDistance(){

    WT nc = 0;
    for(IT j = 0; j < this->heapSize; ++j){
      nc += this->values[j];

      //cout << "index:" << this->indices[j] << " distance:" << this->values[j] << endl;
    }
    return nc;
  }

  //returns the new center of the cluster.
  bool getNewCenters(WT *center, WT **coords, int dimension){
    bool moved = false;
    for(int i = 0; i < dimension; ++i){
      WT nc = 0;
      for(IT j = 0; j < this->heapSize; ++j){
        IT k = this->indices[j];
        //cout << "i:" << i << " dim:" << dimension << " k:" << k << " heapSize:" << heapSize << endl;
        nc += coords[i][k];
      }
      nc /= this->heapSize;
      moved = (ZOLTAN2_ABS(center[i] - nc) > this->_EPSILON || moved );
      center[i] = nc;

    }
    return moved;
  }

  void copyCoordinates(IT *permutation){
    for(IT i = 0; i < this->heapSize; ++i){
      permutation[i] = this->indices[i];
    }
  }
};

template <class IT, class WT>
class KMeansCluster{

  int dimension;
  KmeansHeap<IT,WT> closestPoints;

public:
  WT *center;
  ~KMeansCluster(){
    freeArray<WT>(center);
  }

  void setParams(int dimension_, int heapsize){
    this->dimension = dimension_;
    this->center = allocMemory<WT>(dimension_);
    this->closestPoints.setHeapsize(heapsize);
  }

  void clearHeap(){
    this->closestPoints.initValues();
  }

  bool getNewCenters( WT **coords){
    return this->closestPoints.getNewCenters(center, coords, dimension);
  }

  //returns the distance of the coordinate to the center.
  //also adds it to the heap.
  WT getDistance(IT index, WT **elementCoords){
    WT distance = 0;
    for (int i = 0; i < this->dimension; ++i){
      WT d = (center[i] - elementCoords[i][index]);
      distance += d * d;
    }
    distance = pow(distance, WT(1.0 / this->dimension));
    closestPoints.addPoint(index, distance);
    return distance;
  }

  WT getDistanceToCenter(){
    return closestPoints.getTotalDistance();
  }

  void copyCoordinates(IT *permutation){
    closestPoints.copyCoordinates(permutation);
  }
};

template <class IT, class WT>
class KMeansAlgorithm{

  int dim;
  IT numElements;
  WT **elementCoords;
  IT numClusters;
  IT required_elements;
  KMeansCluster <IT,WT> *clusters;
  WT *maxCoordinates;
  WT *minCoordinates;
public:
  ~KMeansAlgorithm(){
    freeArray<KMeansCluster <IT,WT> >(clusters);
    freeArray<WT>(maxCoordinates);
    freeArray<WT>(minCoordinates);
  }

  KMeansAlgorithm(
      int dim_ ,
      IT numElements_,
      WT **elementCoords_,
      IT required_elements_):
        dim(dim_),
        numElements(numElements_),
        elementCoords(elementCoords_),
        numClusters ((1 << dim_) + 1),
        required_elements(required_elements_)
  {
    this->clusters  = allocMemory<KMeansCluster <IT,WT> >(this->numClusters);
    //set dimension and the number of required elements for all clusters.
    for (int i = 0; i < numClusters; ++i){
      this->clusters[i].setParams(this->dim, this->required_elements);
    }

    this->maxCoordinates = allocMemory <WT> (this->dim);
    this->minCoordinates = allocMemory <WT> (this->dim);

    //obtain the min and max coordiantes for each dimension.
    for (int j = 0; j < dim; ++j){
      this->minCoordinates[j] = this->maxCoordinates[j] = this->elementCoords[j][0];
      for(IT i = 1; i < numElements; ++i){
        WT t = this->elementCoords[j][i];
        if(t > this->maxCoordinates[j]){
          this->maxCoordinates[j] = t;
        }
        if (t < minCoordinates[j]){
          this->minCoordinates[j] = t;
        }
      }
    }


    //assign initial cluster centers.
    for (int j = 0; j < dim; ++j){
      int mod = (1 << (j+1));
      for (int i = 0; i < numClusters - 1; ++i){
        WT c = 0;
        if ( (i % mod) < mod / 2){
          c = this->maxCoordinates[j];
          //cout << "i:" << i << " j:" << j << " setting max:" << c << endl;
        }
        else {
          c = this->minCoordinates[j];
        }
        this->clusters[i].center[j] = c;
      }
    }

    //last cluster center is placed to middle.
    for (int j = 0; j < dim; ++j){
      this->clusters[numClusters - 1].center[j] = (this->maxCoordinates[j] + this->minCoordinates[j]) / 2;
    }


    /*
  for (int i = 0; i < numClusters; ++i){
      //cout << endl << "cluster:" << i << endl << "\t";
      for (int j = 0; j < dim; ++j){
    cout << this->clusters[i].center[j] << " ";
      }
  }
     */
  }

  //performs kmeans clustering of coordinates.
  void kmeans(){
    for(int it = 0; it < 10; ++it){
      //cout << "it:" << it << endl;
      for (IT j = 0; j < this->numClusters; ++j){
        this->clusters[j].clearHeap();
      }
      for (IT i = 0; i < this->numElements; ++i){
        //cout << "i:" << i << " numEl:" << this->numElements << endl;
        for (IT j = 0; j < this->numClusters; ++j){
          //cout << "j:" << j << " numClusters:" << this->numClusters << endl;
          this->clusters[j].getDistance(i,this->elementCoords);
        }
      }
      bool moved = false;
      for (IT j = 0; j < this->numClusters; ++j){
        moved =(this->clusters[j].getNewCenters(this->elementCoords) || moved );
      }
      if (!moved){
        break;
      }
    }


  }

  //finds the cluster in which the coordinates are the closest to each other.
  void getMinDistanceCluster(IT *procPermutation){

    WT minDistance = this->clusters[0].getDistanceToCenter();
    IT minCluster = 0;
    //cout << "j:" << 0 << " minDistance:" << minDistance << " minTmpDistance:" << minDistance<< " minCluster:" << minCluster << endl;
    for (IT j = 1; j < this->numClusters; ++j){
      WT minTmpDistance = this->clusters[j].getDistanceToCenter();
      //cout << "j:" << j << " minDistance:" << minDistance << " minTmpDistance:" << minTmpDistance<< " minCluster:" << minCluster << endl;
      if(minTmpDistance < minDistance){
        minDistance = minTmpDistance;
        minCluster = j;
      }
    }

    //cout << "minCluster:" << minCluster << endl;
    this->clusters[minCluster].copyCoordinates(procPermutation);
  }
};



#define MINOF(a,b) (((a)<(b))?(a):(b))

template <typename T>
void fillContinousArray(T *arr, size_t arrSize, T *val){
  if(val == NULL){

#ifdef HAVE_ZOLTAN2_OMP
#pragma omp parallel for
#endif
    for(size_t i = 0; i < arrSize; ++i){
      arr[i] = i;
    }

  }
  else {
    T v = *val;
#ifdef HAVE_ZOLTAN2_OMP
#pragma omp parallel for
#endif
    for(size_t i = 0; i < arrSize; ++i){
      //cout << "writing to i:" << i << " arr:" << arrSize << endl;
      arr[i] = v;
    }
  }
}

template <typename part_t, typename pcoord_t>
class CommunicationModel{
protected:
  double commCost;
public:

  part_t no_procs; //the number of processors
  part_t no_tasks;  //the number of taks.
  CommunicationModel(): commCost(),no_procs(0), no_tasks(0){}
  CommunicationModel(part_t no_procs_, part_t no_tasks_):
    commCost(),
    no_procs(no_procs_),
    no_tasks(no_tasks_){}
  virtual ~CommunicationModel(){}
  part_t getNProcs() const{
    return this->no_procs;
  }
  part_t getNTasks()const{
    return this->no_tasks;
  }


  void calculateCommunicationCost(
      part_t *task_to_proc,
      part_t *task_communication_xadj,
      part_t *task_communication_adj,
      pcoord_t *task_communication_edge_weight){

    double totalCost = 0;

    part_t commCount = 0;
    for (part_t task = 0; task < this->no_tasks; ++task){
      int assigned_proc = task_to_proc[task];
      //cout << "task:" << task << endl;
      part_t task_adj_begin = task_communication_xadj[task];
      part_t task_adj_end = task_communication_xadj[task+1];

      commCount += task_adj_end - task_adj_begin;
      //cout << "task:" << task << " proc:" << assigned_proc << endl;
      for (part_t task2 = task_adj_begin; task2 < task_adj_end; ++task2){

        //cout << "task2:" << task2 << endl;
        part_t neighborTask = task_communication_adj[task2];
        //cout << "neighborTask :" << neighborTask  << endl;
        int neighborProc = task_to_proc[neighborTask];

        double distance = getProcDistance(assigned_proc, neighborProc);

        if (task_communication_edge_weight == NULL){
          totalCost += distance ;
        }
        else {
          totalCost += distance * task_communication_edge_weight[task2];

          /*
          std::cout <<  "\ttask:" << task << " assigned_proc:" << assigned_proc <<
                        "task2:" << task << " neighborProc:" << neighborProc <<
                        " d:" << distance << " task_communication_edge_weight[task2]:" << task_communication_edge_weight[task2] <<
                        " wh:" << distance * task_communication_edge_weight[task2] <<
                        std::endl;
          */
        }
      }
    }

    this->commCost = totalCost;// commCount;
  }

  double getCommunicationCostMetric(){
    return this->commCost;
  }

  virtual double getProcDistance(int procId1, int procId2) const = 0;

  virtual void getMapping(
      int myRank,
      const RCP<const Environment> &env,
      ArrayRCP <part_t> &proc_to_task_xadj, //  = allocMemory<part_t> (this->no_procs+1); //holds the pointer to the task array
      ArrayRCP <part_t> &proc_to_task_adj, // = allocMemory<part_t>(this->no_tasks); //holds the indices of tasks wrt to proc_to_task_xadj array.
      ArrayRCP <part_t> &task_to_proc //allocMemory<part_t>(this->no_tasks); //holds the processors mapped to tasks.
      ,const Teuchos::RCP <const Teuchos::Comm<int> > comm_
  ) const = 0;
};
template <typename pcoord_t,  typename tcoord_t, typename part_t>
class CoordinateCommunicationModel:public CommunicationModel<part_t, pcoord_t> {
public:
  //private:
  int proc_coord_dim; //dimension of the processors
  pcoord_t **proc_coords; //the processor coordinates. allocated outside of the class.
  int task_coord_dim; //dimension of the tasks coordinates.
  tcoord_t **task_coords; //the task coordinates allocated outside of the class.
  int partArraySize;
  part_t *partNoArray;

  int *machine_extent;
  bool *machine_extent_wrap_around;
  const MachineRepresentation<pcoord_t,part_t> *machine;

  int num_ranks_per_node;
  bool divide_to_prime_first;

  //public:
  CoordinateCommunicationModel():
    CommunicationModel<part_t, pcoord_t>(),
    proc_coord_dim(0),
    proc_coords(0),
    task_coord_dim(0),
    task_coords(0),
    partArraySize(-1),
    partNoArray(NULL),
    machine_extent(NULL),
    machine_extent_wrap_around(NULL),
    machine(NULL),
    num_ranks_per_node(1),
    divide_to_prime_first(false){}

  virtual ~CoordinateCommunicationModel(){}

  CoordinateCommunicationModel(
      int pcoord_dim_,
      pcoord_t **pcoords_,
      int tcoord_dim_,
      tcoord_t **tcoords_,
      part_t no_procs_,
      part_t no_tasks_,
      int *machine_extent_,
      bool *machine_extent_wrap_around_,
      const MachineRepresentation<pcoord_t,part_t> *machine_ = NULL
  ):
    CommunicationModel<part_t, pcoord_t>(no_procs_, no_tasks_),
    proc_coord_dim(pcoord_dim_), proc_coords(pcoords_),
    task_coord_dim(tcoord_dim_), task_coords(tcoords_),
    partArraySize(-1),
    partNoArray(NULL),
    machine_extent(machine_extent_),
    machine_extent_wrap_around(machine_extent_wrap_around_),
    machine(machine_),
    num_ranks_per_node(1),
    divide_to_prime_first(false){
  }


  void setPartArraySize(int psize){
    this->partArraySize = psize;
  }
  void setPartArray(part_t *pNo){
    this->partNoArray = pNo;
  }

  void getClosestSubset(part_t *proc_permutation, part_t nprocs, part_t ntasks) const{
    //currently returns a random subset.

    part_t minCoordDim = MINOF(this->task_coord_dim, this->proc_coord_dim);
    KMeansAlgorithm<part_t, pcoord_t > kma(
        minCoordDim, nprocs,
        this->proc_coords, ntasks);

    kma.kmeans();
    kma.getMinDistanceCluster(proc_permutation);

    for(int i = ntasks; i < nprocs; ++i){
      proc_permutation[i] = -1;
    }
    /*
  //fill array.
  fillContinousArray<part_t>(proc_permutation, nprocs, NULL);
  int _u_umpa_seed = 847449649;
  srand (time(NULL));
  int a = rand() % 1000 + 1;
  _u_umpa_seed -= a;
  //permute array randomly.
  update_visit_order(proc_permutation, nprocs,_u_umpa_seed, 1);
     */
  }

  //temporary, necessary for random permutation.
  static part_t umpa_uRandom(part_t l, int &_u_umpa_seed)
  {
    int   a = 16807;
    int   m = 2147483647;
    int   q = 127773;
    int   r = 2836;
    int   lo, hi, test;
    double d;

    lo = _u_umpa_seed % q;
    hi = _u_umpa_seed / q;
    test = (a*lo)-(r*hi);
    if (test>0)
      _u_umpa_seed = test;
    else
      _u_umpa_seed = test + m;
    d = (double) ((double) _u_umpa_seed / (double) m);
    return (part_t) (d*(double)l);
  }

  virtual double getProcDistance(int procId1, int procId2) const{
    pcoord_t distance = 0;
    if (machine == NULL){
      for (int i = 0 ; i < this->proc_coord_dim; ++i){
        double d = ZOLTAN2_ABS(proc_coords[i][procId1] - proc_coords[i][procId2]);
        if (machine_extent_wrap_around && machine_extent_wrap_around[i]){
          if (machine_extent[i] - d < d){
            d = machine_extent[i] - d;
          }
        }
        distance += d;
      }
    }
    else {
      this->machine->getHopCount(procId1, procId2, distance);
    }

    return distance;
  }


  //temporary, does random permutation.
  void update_visit_order(part_t* visitOrder, part_t n, int &_u_umpa_seed, part_t rndm) {
    part_t *a = visitOrder;


    if (rndm){
      part_t i, u, v, tmp;

      if (n <= 4)
        return;

      //srand ( time(NULL) );

      //_u_umpa_seed = _u_umpa_seed1 - (rand()%100);
      for (i=0; i<n; i+=16)
      {
        u = umpa_uRandom(n-4, _u_umpa_seed);
        v = umpa_uRandom(n-4, _u_umpa_seed);

        // FIXME (mfh 30 Sep 2015) This requires including Zoltan2_AlgMultiJagged.hpp.

        ZOLTAN2_ALGMULTIJAGGED_SWAP(a[v], a[u], tmp);
        ZOLTAN2_ALGMULTIJAGGED_SWAP(a[v+1], a[u+1], tmp);
        ZOLTAN2_ALGMULTIJAGGED_SWAP(a[v+2], a[u+2], tmp);
        ZOLTAN2_ALGMULTIJAGGED_SWAP(a[v+3], a[u+3], tmp);

      }
    }
    else {
      part_t i, end = n / 4;

      for (i=1; i<end; i++)
      {
        part_t j=umpa_uRandom(n-i, _u_umpa_seed);
        part_t t=a[j];
        a[j] = a[n-i];
        a[n-i] = t;
      }
    }
    //PermuteInPlace(visitOrder, n);
  }



  virtual void getMapping(
      int myRank,
      const RCP<const Environment> &env,
      ArrayRCP <part_t> &rcp_proc_to_task_xadj, //  = allocMemory<part_t> (this->no_procs+1); //holds the pointer to the task array
      ArrayRCP <part_t> &rcp_proc_to_task_adj, // = allocMemory<part_t>(this->no_tasks); //holds the indices of tasks wrt to proc_to_task_xadj array.
      ArrayRCP <part_t> &rcp_task_to_proc //allocMemory<part_t>(this->no_tasks); //holds the processors mapped to tasks.
      ,const Teuchos::RCP <const Teuchos::Comm<int> > comm_
  ) const{

    rcp_proc_to_task_xadj = ArrayRCP <part_t> (this->no_procs+1);
    rcp_proc_to_task_adj = ArrayRCP <part_t> (this->no_tasks);
    rcp_task_to_proc = ArrayRCP <part_t> (this->no_tasks);

    part_t *proc_to_task_xadj = rcp_proc_to_task_xadj.getRawPtr(); //holds the pointer to the task array
    part_t *proc_to_task_adj = rcp_proc_to_task_adj.getRawPtr(); //holds the indices of tasks wrt to proc_to_task_xadj array.
    part_t *task_to_proc = rcp_task_to_proc.getRawPtr(); //holds the processors mapped to tasks.);


    part_t invalid = 0;
    fillContinousArray<part_t> (proc_to_task_xadj, this->no_procs+1, &invalid);

    //obtain the number of parts that should be divided.
    part_t num_parts = MINOF(this->no_procs, this->no_tasks);
    //obtain the min coordinate dim.
    //No more want to do min coord dim. If machine dimension > task_dim,
    //we end up with a long line.
    //part_t minCoordDim = MINOF(this->task_coord_dim, this->proc_coord_dim);

    int recursion_depth = partArraySize;
    //if(partArraySize < minCoordDim) recursion_depth = minCoordDim;
    if (partArraySize == -1){

      if (divide_to_prime_first){
        //it is difficult to estimate the number of steps in this case as each branch will have different depth.
        //The worst case happens when all prime factors are 3s. P = 3^n, n recursion depth will divide parts to 2x and x
        //and n recursion depth with divide 2x into x and x.
        //set it to upperbound here.
        //we could calculate the exact value here as well, but the partitioning algorithm skips further ones anyways.
        recursion_depth = log(float(this->no_procs)) / log(2.0) * 2 + 1;
      }
      else {
        recursion_depth = log(float(this->no_procs)) / log(2.0) + 1;
      }
    }


    int taskPerm = z2Fact<int>(this->task_coord_dim); //get the number of different permutations for task dimension ordering
    int procPerm = z2Fact<int>(this->proc_coord_dim); //get the number of different permutations for proc dimension ordering

    int permutations =  taskPerm * procPerm; //total number of permutations
    //now add the ones, where we divide the processors with longest dimension,
    //but task with order.
    permutations +=  taskPerm;
    //and divide tasks with longest dimension, and processors with order.
    permutations += procPerm; //total number of permutations
    //and both with longest dimension.
    permutations += 1;
    //add one also that partitions based the longest dimension.

    //holds the pointers to proc_adjList
    part_t *proc_xadj = allocMemory<part_t> (num_parts+1);
    //holds the processors in parts according to the result of partitioning algorithm.
    //the processors assigned to part x is at proc_adjList[ proc_xadj[x] : proc_xadj[x+1] ]
    part_t *proc_adjList = allocMemory<part_t>(this->no_procs);


    part_t used_num_procs = this->no_procs;
    if(this->no_procs > this->no_tasks){
      //obtain the subset of the processors that are closest to each other.
      this->getClosestSubset(proc_adjList, this->no_procs, this->no_tasks);
      used_num_procs = this->no_tasks;
    }
    else {
      fillContinousArray<part_t>(proc_adjList,this->no_procs, NULL);
    }

    int myPermutation = myRank % permutations; //the index of the permutation
    bool task_partition_along_longest_dim = false;
    bool proc_partition_along_longest_dim = false;


    int myProcPerm = 0;
    int myTaskPerm = 0;

    if (myPermutation == 0){
      task_partition_along_longest_dim = true;
      proc_partition_along_longest_dim = true;
    }
    else {
      --myPermutation;
      if (myPermutation < taskPerm){
        proc_partition_along_longest_dim = true;
        myTaskPerm  = myPermutation; // the index of the task permutation
      }
      else{
        myPermutation -= taskPerm;
        if (myPermutation < procPerm){
          task_partition_along_longest_dim = true;
          myProcPerm  = myPermutation; // the index of the task permutation
        }
        else {
          myPermutation -= procPerm;
          myProcPerm = myPermutation % procPerm; // the index of the proc permutation
          myTaskPerm = myPermutation / procPerm; // the index of the task permutation
        }
      }
    }




    /*
    if (task_partition_along_longest_dim && proc_partition_along_longest_dim){
      std::cout <<"me:" << myRank << " task:longest proc:longest" << " numPerms:" << permutations << std::endl;
    }
    else if (proc_partition_along_longest_dim){
      std::cout <<"me:" << myRank << " task:" <<  myTaskPerm << " proc:longest" << " numPerms:" << permutations << std::endl;
    }
    else if (task_partition_along_longest_dim){
      std::cout <<"me:" << myRank << " task: longest" << " proc:" <<  myProcPerm  << " numPerms:" << permutations << std::endl;
    }
    else {
      std::cout <<"me:" << myRank << " task:" <<  myTaskPerm << " proc:" <<  myProcPerm  << " numPerms:" << permutations << std::endl;
    }
    */



    int *permutation = allocMemory<int> ((this->proc_coord_dim > this->task_coord_dim)
        ? this->proc_coord_dim : this->task_coord_dim);

    //get the permutation order from the proc permutation index.
    ithPermutation<int>(this->proc_coord_dim, myProcPerm, permutation);

    /*
    //reorder the coordinate dimensions.
    pcoord_t **pcoords = allocMemory<pcoord_t *> (this->proc_coord_dim);
    for(int i = 0; i < this->proc_coord_dim; ++i){
      pcoords[i] = this->proc_coords[permutation[i]];
      //cout << permutation[i] << " ";
    }
    */
    int procdim  = this->proc_coord_dim;
    pcoord_t **pcoords = this->proc_coords;
    /*
    int procdim  = this->proc_coord_dim;
    procdim  = 6;
    //reorder the coordinate dimensions.
    pcoord_t **pcoords = allocMemory<pcoord_t *> (procdim);
    for(int i = 0; i < procdim; ++i){
      pcoords[i] = new pcoord_t[used_num_procs] ;//this->proc_coords[permutation[i]];
    }

    for (int k = 0; k < used_num_procs ; k++){
      pcoords[0][k] = (int (this->proc_coords[0][k]) / 2) * 64;
      pcoords[3][k] = (int (this->proc_coords[0][k]) % 2) * 8 ;

      pcoords[1][k] = (int (this->proc_coords[1][k])  / 2) * 8 * 2400;
      pcoords[4][k] = (int (this->proc_coords[1][k])  % 2) * 8;
      pcoords[2][k] = ((int (this->proc_coords[2][k])) / 8) * 160;
      pcoords[5][k] = ((int (this->proc_coords[2][k])) % 8) * 5;

      //if (this->proc_coords[0][k] == 40 && this->proc_coords[1][k] == 8 && this->proc_coords[2][k] == 48){
      if (this->proc_coords[0][k] == 5 && this->proc_coords[1][k] == 0 && this->proc_coords[2][k] == 10){
        std::cout << "pcoords[0][k]:" << pcoords[0][k] <<
                  "pcoords[1][k]:" << pcoords[1][k] <<
                  "pcoords[2][k]:" << pcoords[2][k] <<
                  "pcoords[3][k]:" << pcoords[3][k] <<
                  "pcoords[4][k]:" << pcoords[4][k] <<
                  "pcoords[5][k]:" << pcoords[5][k] << std::endl;
      }
      else if ( pcoords[0][k] == 64 && pcoords[1][k] == 0 && pcoords[2][k] == 160 &&
                pcoords[3][k]==16 && pcoords[4][k] == 0 && pcoords[5][k] == 10){
        std::cout << "this->proc_coords[0][k]:" << this->proc_coords[0][k] <<
                      "this->proc_coords[1][k]:" << this->proc_coords[1][k] <<
                      "this->proc_coords[2][k]:" << this->proc_coords[2][k] << std::endl;
      }

    }
    */


    //if (partNoArray == NULL) std::cout << "partNoArray is null" << std::endl;
    //std::cout << "recursion_depth:" << recursion_depth << " partArraySize:" << partArraySize << std::endl;
    //do the partitioning and renumber the parts.
    env->timerStart(MACRO_TIMERS, "Mapping - Proc Partitioning");

    AlgMJ<pcoord_t, part_t, part_t, part_t> mj_partitioner;
    mj_partitioner.sequential_task_partitioning(
        env,
        this->no_procs,
        used_num_procs,
        num_parts,
        procdim,
        //minCoordDim,
        pcoords,//this->proc_coords,
        proc_adjList,
        proc_xadj,
        recursion_depth,
        partNoArray,
        proc_partition_along_longest_dim//, false
        ,num_ranks_per_node
        ,divide_to_prime_first
    );
    env->timerStop(MACRO_TIMERS, "Mapping - Proc Partitioning");
    //comm_->barrier();
    //std::cout << "mj_partitioner.for procs over" << std::endl;


    //freeArray<pcoord_t *> (pcoords);


    part_t *task_xadj = allocMemory<part_t> (num_parts+1);
    part_t *task_adjList = allocMemory<part_t>(this->no_tasks);
    //fill task_adjList st: task_adjList[i] <- i.
    fillContinousArray<part_t>(task_adjList,this->no_tasks, NULL);

    //get the permutation order from the task permutation index.
    ithPermutation<int>(this->task_coord_dim, myTaskPerm, permutation);

    //reorder task coordinate dimensions.
    tcoord_t **tcoords = allocMemory<tcoord_t *> (this->task_coord_dim);
    for(int i = 0; i < this->task_coord_dim; ++i){
      tcoords[i] = this->task_coords[permutation[i]];
    }


    env->timerStart(MACRO_TIMERS, "Mapping - Task Partitioning");
    //partitioning of tasks
    mj_partitioner.sequential_task_partitioning(
        env,
        this->no_tasks,
        this->no_tasks,
        num_parts,
        this->task_coord_dim,
        //minCoordDim,
        tcoords, //this->task_coords,
        task_adjList,
        task_xadj,
        recursion_depth,
        partNoArray,
        task_partition_along_longest_dim
        ,num_ranks_per_node
        ,divide_to_prime_first
        //,"task_partitioning"
        //, false//(myRank == 6)
    );
    env->timerStop(MACRO_TIMERS, "Mapping - Task Partitioning");

    //std::cout << "myrank:" << myRank << std::endl;
    //comm_->barrier();
    //std::cout << "mj_partitioner.sequential_task_partitioning over" << std::endl;

    freeArray<pcoord_t *> (tcoords);
    freeArray<int> (permutation);


    //filling proc_to_task_xadj, proc_to_task_adj, task_to_proc arrays.
    for(part_t i = 0; i < num_parts; ++i){

      part_t proc_index_begin = proc_xadj[i];
      part_t task_begin_index = task_xadj[i];
      part_t proc_index_end = proc_xadj[i+1];
      part_t task_end_index = task_xadj[i+1];


      if(proc_index_end - proc_index_begin != 1){
        std::cerr << "Error at partitioning of processors" << std::endl;
        std::cerr << "PART:" << i << " is assigned to " << proc_index_end - proc_index_begin << " processors." << std::endl;
        exit(1);
      }
      part_t assigned_proc = proc_adjList[proc_index_begin];
      proc_to_task_xadj[assigned_proc] = task_end_index - task_begin_index;
    }


    //holds the pointer to the task array
    //convert proc_to_task_xadj to CSR index array
    part_t *proc_to_task_xadj_work = allocMemory<part_t> (this->no_procs);
    part_t sum = 0;
    for(part_t i = 0; i < this->no_procs; ++i){
      part_t tmp = proc_to_task_xadj[i];
      proc_to_task_xadj[i] = sum;
      sum += tmp;
      proc_to_task_xadj_work[i] = sum;
    }
    proc_to_task_xadj[this->no_procs] = sum;

    for(part_t i = 0; i < num_parts; ++i){

      part_t proc_index_begin = proc_xadj[i];
      part_t task_begin_index = task_xadj[i];
      part_t task_end_index = task_xadj[i+1];

      part_t assigned_proc = proc_adjList[proc_index_begin];

      for (part_t j = task_begin_index; j < task_end_index; ++j){
        part_t taskId = task_adjList[j];

        task_to_proc[taskId] = assigned_proc;

        proc_to_task_adj [ --proc_to_task_xadj_work[assigned_proc] ] = taskId;
      }
    }

    /*
    if (myPermutation == 0){
      std::ofstream gnuPlotCode ("mymapping.out", std::ofstream::out);


      for(part_t i = 0; i < num_parts; ++i){

        part_t proc_index_begin = proc_xadj[i];
        part_t proc_index_end = proc_xadj[i+1];


        if(proc_index_end - proc_index_begin != 1){
          std::cerr << "Error at partitioning of processors" << std::endl;
          std::cerr << "PART:" << i << " is assigned to " << proc_index_end - proc_index_begin << " processors." << std::endl;
          exit(1);
        }

        part_t assigned_proc = proc_adjList[proc_index_begin];
        gnuPlotCode << "Rank:" << i << " " <<
            this->proc_coords[0][assigned_proc] << " " << this->proc_coords[1][assigned_proc] << " " << this->proc_coords[2][assigned_proc] <<
             " " << pcoords[0][assigned_proc] << " " << pcoords[1][assigned_proc] <<
             " " << pcoords[2][assigned_proc] << " " << pcoords[3][assigned_proc] <<
            std::endl;

      }


      gnuPlotCode << "Machine Extent:" << std::endl;
      //filling proc_to_task_xadj, proc_to_task_adj, task_to_proc arrays.
      for(part_t i = 0; i < num_parts; ++i){

        part_t proc_index_begin = proc_xadj[i];
        part_t proc_index_end = proc_xadj[i+1];


        if(proc_index_end - proc_index_begin != 1){
          std::cerr << "Error at partitioning of processors" << std::endl;
          std::cerr << "PART:" << i << " is assigned to " << proc_index_end - proc_index_begin << " processors." << std::endl;
          exit(1);
        }

        part_t assigned_proc = proc_adjList[proc_index_begin];
        gnuPlotCode << "Rank:" << i << " " << this->proc_coords[0][assigned_proc] << " " << this->proc_coords[1][assigned_proc] << " " << this->proc_coords[2][assigned_proc] << std::endl;

      }
      gnuPlotCode.close();
    }
    */

    freeArray<part_t>(proc_to_task_xadj_work);
    freeArray<part_t>(task_xadj);
    freeArray<part_t>(task_adjList);
    freeArray<part_t>(proc_xadj);
    freeArray<part_t>(proc_adjList);
  }

};

template <typename Adapter, typename part_t>
class CoordinateTaskMapper:public PartitionMapping<Adapter>{
protected:

#ifndef DOXYGEN_SHOULD_SKIP_THIS

  typedef typename Adapter::scalar_t pcoord_t;
  typedef typename Adapter::scalar_t tcoord_t;
  typedef typename Adapter::scalar_t scalar_t;
  typedef typename Adapter::lno_t lno_t;

#endif

  //RCP<const Environment> env;
  ArrayRCP<part_t> proc_to_task_xadj; //  = allocMemory<part_t> (this->no_procs+1); //holds the pointer to the task array
  ArrayRCP<part_t> proc_to_task_adj; // = allocMemory<part_t>(this->no_tasks); //holds the indices of tasks wrt to proc_to_task_xadj array.
  ArrayRCP<part_t> task_to_proc; //allocMemory<part_t>(this->no_procs); //holds the processors mapped to tasks.
  ArrayRCP<part_t> local_task_to_rank; //allocMemory<part_t>(this->no_procs); //holds the processors mapped to tasks.

  bool isOwnerofModel;
  CoordinateCommunicationModel<pcoord_t,tcoord_t,part_t> *proc_task_comm;
  part_t nprocs;
  part_t ntasks;
  ArrayRCP<part_t> task_communication_xadj;
  ArrayRCP<part_t> task_communication_adj;
  ArrayRCP<scalar_t> task_communication_edge_weight;


  void doMapping(int myRank, const Teuchos::RCP <const Teuchos::Comm<int> > comm_){

    if(this->proc_task_comm){
      this->proc_task_comm->getMapping(
          myRank,
          this->env,
          this->proc_to_task_xadj, //  = allocMemory<part_t> (this->no_procs+1); //holds the pointer to the task array
          this->proc_to_task_adj, // = allocMemory<part_t>(this->no_tasks); //holds the indices of tasks wrt to proc_to_task_xadj array.
          this->task_to_proc //allocMemory<part_t>(this->no_procs); //holds the processors mapped to tasks.);
          ,comm_
      );
    }
    else {
      std::cerr << "communicationModel is not specified in the Mapper" << std::endl;
      exit(1);
    }
  }


  RCP<Comm<int> > create_subCommunicator(){
    int procDim = this->proc_task_comm->proc_coord_dim;
    int taskDim = this->proc_task_comm->task_coord_dim;

    int taskPerm = z2Fact<int>(procDim); //get the number of different permutations for task dimension ordering
    int procPerm = z2Fact<int>(taskDim); //get the number of different permutations for proc dimension ordering
    int idealGroupSize =  taskPerm * procPerm; //total number of permutations

    idealGroupSize += taskPerm + procPerm + 1; //for the one that does longest dimension partitioning.

    int myRank = this->comm->getRank();
    int commSize = this->comm->getSize();

    int myGroupIndex = myRank / idealGroupSize;

    int prevGroupBegin = (myGroupIndex - 1)* idealGroupSize;
    if (prevGroupBegin < 0) prevGroupBegin = 0;
    int myGroupBegin = myGroupIndex * idealGroupSize;
    int myGroupEnd = (myGroupIndex + 1) * idealGroupSize;
    int nextGroupEnd = (myGroupIndex + 2)* idealGroupSize;

    if (myGroupEnd > commSize){
      myGroupBegin = prevGroupBegin;
      myGroupEnd = commSize;
    }
    if (nextGroupEnd > commSize){
      myGroupEnd = commSize;
    }
    int myGroupSize = myGroupEnd - myGroupBegin;

    part_t *myGroup = allocMemory<part_t>(myGroupSize);
    for (int i = 0; i < myGroupSize; ++i){
      myGroup[i] = myGroupBegin + i;
    }
    //cout << "me:" << myRank << " myGroupBegin:" << myGroupBegin << " myGroupEnd:" << myGroupEnd << endl;

    ArrayView<const part_t> myGroupView(myGroup, myGroupSize);

    RCP<Comm<int> > subComm = this->comm->createSubcommunicator(myGroupView);
    freeArray<part_t>(myGroup);
    return subComm;
  }


  void getBestMapping(){
    //create the sub group.
    RCP<Comm<int> > subComm = this->create_subCommunicator();
    //calculate cost.
    double myCost = this->proc_task_comm->getCommunicationCostMetric();
    //std::cout << "me:" << this->comm->getRank() << " myCost:" << myCost << std::endl;
    double localCost[2], globalCost[2];

    localCost[0] = myCost;
    localCost[1] = double(subComm->getRank());

    globalCost[1] = globalCost[0] = std::numeric_limits<double>::max();
    Teuchos::Zoltan2_ReduceBestMapping<int,double> reduceBest;
    reduceAll<int, double>(*subComm, reduceBest,
        2, localCost, globalCost);

    int sender = int(globalCost[1]);

    /*
    if ( this->comm->getRank() == 0){
      std::cout << "me:" << localCost[1] <<
            " localcost:" << localCost[0]<<
            " bestcost:" << globalCost[0] <<
            " Sender:" << sender <<
            " procDim" << proc_task_comm->proc_coord_dim <<
            " taskDim:" << proc_task_comm->task_coord_dim << std::endl;
    }
    */
    //cout << "me:" << localCost[1] << " localcost:" << localCost[0]<< " bestcost:" << globalCost[0] << endl;
    //cout << "me:" << localCost[1] << " proc:" << globalCost[1] << endl;
    broadcast (*subComm, sender, this->ntasks, this->task_to_proc.getRawPtr());
    broadcast (*subComm, sender, this->nprocs, this->proc_to_task_xadj.getRawPtr());
    broadcast (*subComm, sender, this->ntasks, this->proc_to_task_adj.getRawPtr());
  }



  //write mapping to gnuPlot code to visualize.
  void writeMapping(){
    std::ofstream gnuPlotCode ("gnuPlot.plot", std::ofstream::out);

    int mindim = MINOF(proc_task_comm->proc_coord_dim, proc_task_comm->task_coord_dim);
    std::string ss = "";
    for(part_t i = 0; i < this->nprocs; ++i){

      std::string procFile = Teuchos::toString<int>(i) + "_mapping.txt";
      if (i == 0){
        gnuPlotCode << "plot \"" << procFile << "\"\n";
      }
      else {
        gnuPlotCode << "replot \"" << procFile << "\"\n";
      }

      std::ofstream inpFile (procFile.c_str(), std::ofstream::out);

      std::string gnuPlotArrow = "set arrow from ";
      for(int j = 0; j <  mindim; ++j){
        if (j == mindim - 1){
          inpFile << proc_task_comm->proc_coords[j][i];
          gnuPlotArrow += Teuchos::toString<float>(proc_task_comm->proc_coords[j][i]);

        }
        else {
          inpFile << proc_task_comm->proc_coords[j][i] << " ";
          gnuPlotArrow += Teuchos::toString<float>(proc_task_comm->proc_coords[j][i]) +",";
        }
      }
      gnuPlotArrow += " to ";


      inpFile << std::endl;
      ArrayView<part_t> a = this->getAssignedTasksForProc(i);
      for(int k = 0; k <  a.size(); ++k){
        int j = a[k];
        //cout << "i:" << i << " j:"
        std::string gnuPlotArrow2 = gnuPlotArrow;
        for(int z = 0; z <  mindim; ++z){
          if(z == mindim - 1){

            //cout << "z:" << z << " j:" <<  j << " " << proc_task_comm->task_coords[z][j] << endl;
            inpFile << proc_task_comm->task_coords[z][j];
            gnuPlotArrow2 += Teuchos::toString<float>(proc_task_comm->task_coords[z][j]);
          }
          else{
            inpFile << proc_task_comm->task_coords[z][j] << " ";
            gnuPlotArrow2 += Teuchos::toString<float>(proc_task_comm->task_coords[z][j]) +",";
          }
        }
        ss += gnuPlotArrow2 + "\n";
        inpFile << std::endl;
      }
      inpFile.close();
    }
    gnuPlotCode << ss;
    gnuPlotCode << "\nreplot\n pause -1 \n";
    gnuPlotCode.close();

  }


  //write mapping to gnuPlot code to visualize.
  void writeMapping2(int myRank){
    std::string rankStr = Teuchos::toString<int>(myRank);
    std::string gnuPlots = "gnuPlot", extentionS = ".plot";
    std::string outF = gnuPlots + rankStr+ extentionS;
    std::ofstream gnuPlotCode ( outF.c_str(), std::ofstream::out);

    CoordinateCommunicationModel<pcoord_t, tcoord_t, part_t> *tmpproc_task_comm =
        static_cast <CoordinateCommunicationModel<pcoord_t, tcoord_t, part_t> * > (proc_task_comm);
    //int mindim = MINOF(tmpproc_task_comm->proc_coord_dim, tmpproc_task_comm->task_coord_dim);
    int mindim = tmpproc_task_comm->proc_coord_dim;
    if (mindim != 3) {
      std::cerr << "Mapping Write is only good for 3 dim" << std::endl;
      return;
    }
    std::string ss = "";
    std::string procs = "";

    std::set < std::tuple<int,int,int,int,int,int> > my_arrows;
    for(part_t origin_rank = 0; origin_rank < this->nprocs; ++origin_rank){
      ArrayView<part_t> a = this->getAssignedTasksForProc(origin_rank);
      if (a.size() == 0){
        continue;
      }

      std::string gnuPlotArrow = "set arrow from ";
      for(int j = 0; j <  mindim; ++j){
        if (j == mindim - 1){
          gnuPlotArrow += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][origin_rank]);
          procs += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][origin_rank]);

        }
        else {
          gnuPlotArrow += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][origin_rank]) +",";
          procs += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][origin_rank])+ " ";
        }
      }
      procs += "\n";

      gnuPlotArrow += " to ";


      for(int k = 0; k < a.size(); ++k){
        int origin_task = a[k];

        for (int nind = task_communication_xadj[origin_task]; nind < task_communication_xadj[origin_task + 1]; ++nind){
          int neighbor_task = task_communication_adj[nind];

          bool differentnode = false;

          int neighbor_rank = this->getAssignedProcForTask(neighbor_task);

          for(int j = 0; j <  mindim; ++j){
            if (int (tmpproc_task_comm->proc_coords[j][origin_rank]) != int (tmpproc_task_comm->proc_coords[j][neighbor_rank])){
              differentnode = true; break;
            }
          }
          std::tuple<int,int,int, int, int, int> foo (
              int (tmpproc_task_comm->proc_coords[0][origin_rank]),
              int (tmpproc_task_comm->proc_coords[1][origin_rank]),
              int (tmpproc_task_comm->proc_coords[2][origin_rank]),
              int (tmpproc_task_comm->proc_coords[0][neighbor_rank]),
              int (tmpproc_task_comm->proc_coords[1][neighbor_rank]),
              int (tmpproc_task_comm->proc_coords[2][neighbor_rank]));


          if (differentnode && my_arrows.find(foo) == my_arrows.end()){
            my_arrows.insert(foo);

            std::string gnuPlotArrow2 = "";
            for(int j = 0; j <  mindim; ++j){
              if(j == mindim - 1){
                gnuPlotArrow2 += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][neighbor_rank]);
              }
              else{
                gnuPlotArrow2 += Teuchos::toString<float>(tmpproc_task_comm->proc_coords[j][neighbor_rank]) +",";
              }
            }
            ss += gnuPlotArrow + gnuPlotArrow2 + " nohead\n";
          }
        }
      }

    }


    std::ofstream procFile ("procPlot.plot", std::ofstream::out);
    procFile << procs << "\n";
    procFile.close();

    //gnuPlotCode << ss;
    if(mindim == 2){
      gnuPlotCode << "plot \"procPlot.plot\" with points pointsize 3\n";
    } else {
      gnuPlotCode << "splot \"procPlot.plot\" with points pointsize 3\n";
    }

    gnuPlotCode << ss << "\nreplot\n pause -1 \n";
    gnuPlotCode.close();
  }


// KDD Need to provide access to algorithm for getPartBoxes
#ifdef gnuPlot
  void writeGnuPlot(
      const Teuchos::Comm<int> *comm_,
      const Zoltan2::PartitioningSolution<Adapter> *soln_,
      int coordDim,
      tcoord_t **partCenters
  ){
    std::string file = "gggnuPlot";
    std::string exten = ".plot";
    std::ofstream mm("2d.txt");
    file += Teuchos::toString<int>(comm_->getRank()) + exten;
    std::ofstream ff(file.c_str());
    //ff.seekg (0, ff.end);
    std::vector <Zoltan2::coordinateModelPartBox <tcoord_t, part_t> > outPartBoxes = ((Zoltan2::PartitioningSolution<Adapter> *)soln_)->getPartBoxesView();

    for (part_t i = 0; i < this->ntasks;++i){
      outPartBoxes[i].writeGnuPlot(ff, mm);
    }
    if (coordDim == 2){
      ff << "plot \"2d.txt\"" << std::endl;
      //ff << "\n pause -1" << endl;
    }
    else {
      ff << "splot \"2d.txt\"" << std::endl;
      //ff << "\n pause -1" << endl;
    }
    mm.close();

    ff << "set style arrow 5 nohead size screen 0.03,15,135 ls 1" << std::endl;
    for (part_t i = 0; i < this->ntasks;++i){
      part_t pb = task_communication_xadj[i];
      part_t pe = task_communication_xadj[i+1];
      for (part_t p = pb; p < pe; ++p){
        part_t n = task_communication_adj[p];

        //cout << "i:" << i << " n:" << n << endl;
        std::string arrowline = "set arrow from ";
        for (int j = 0; j < coordDim - 1; ++j){
          arrowline += Teuchos::toString<tcoord_t>(partCenters[j][n]) + ",";
        }
        arrowline += Teuchos::toString<tcoord_t>(partCenters[coordDim -1][n]) + " to ";


        for (int j = 0; j < coordDim - 1; ++j){
          arrowline += Teuchos::toString<tcoord_t>(partCenters[j][i]) + ",";
        }
        arrowline += Teuchos::toString<tcoord_t>(partCenters[coordDim -1][i]) + " as 5\n";

        //cout << "arrow:" << arrowline << endl;
        ff << arrowline;
      }
    }

    ff << "replot\n pause -1" << std::endl;
    ff.close();
  }
#endif // gnuPlot

public:

  void getProcTask(part_t* &proc_to_task_xadj_, part_t* &proc_to_task_adj_){
    proc_to_task_xadj_ = this->proc_to_task_xadj.getRawPtr();
    proc_to_task_adj_ = this->proc_to_task_adj.getRawPtr();
  }

  virtual void map(const RCP<MappingSolution<Adapter> > &mappingsoln) {

    // Mapping was already computed in the constructor; we need to store it
    // in the solution.
    mappingsoln->setMap_RankForLocalElements(local_task_to_rank);

    // KDDKDD TODO:  Algorithm is also creating task_to_proc, which maybe 
    // KDDKDD is not needed once we use MappingSolution to answer queries 
    // KDDKDD instead of this algorithm.  
    // KDDKDD Ask Mehmet:  what is the most efficient way to get the answer
    // KDDKDD out of CoordinateTaskMapper and into the MappingSolution?
  }


  virtual ~CoordinateTaskMapper(){
    //freeArray<part_t> (proc_to_task_xadj);
    //freeArray<part_t> (proc_to_task_adj);
    //freeArray<part_t> (task_to_proc);
    if(this->isOwnerofModel){
      delete this->proc_task_comm;
    }
  }

  void create_local_task_to_rank(
      const lno_t num_local_coords,
      const part_t *local_coord_parts,
      const ArrayRCP<part_t> task_to_proc_){
    local_task_to_rank = ArrayRCP <part_t> (num_local_coords);

    for (lno_t i = 0; i < num_local_coords; ++i){
      part_t local_coord_part = local_coord_parts[i];
      part_t rank_index = task_to_proc_[local_coord_part];
      local_task_to_rank[i] = rank_index;
    }
  }



  CoordinateTaskMapper(
      const Teuchos::RCP <const Teuchos::Comm<int> > comm_,
      const Teuchos::RCP <const MachineRepresentation<pcoord_t,part_t> > machine_,
      const Teuchos::RCP <const Adapter> input_adapter_,
      const Teuchos::RCP <const Zoltan2::PartitioningSolution<Adapter> > soln_,
      const Teuchos::RCP <const Environment> envConst,
      bool is_input_adapter_distributed = true,
      int num_ranks_per_node = 1,
      bool divide_to_prime_first = false, bool reduce_best_mapping = true):
        PartitionMapping<Adapter> (comm_, machine_, input_adapter_, soln_, envConst),
        proc_to_task_xadj(0),
        proc_to_task_adj(0),
        task_to_proc(0),
        isOwnerofModel(true),
        proc_task_comm(0),
        task_communication_xadj(0),
        task_communication_adj(0),
        task_communication_edge_weight(0){
    using namespace Teuchos;
    typedef typename Adapter::base_adapter_t ctm_base_adapter_t;

    RCP<Zoltan2::GraphModel<ctm_base_adapter_t> > graph_model_;
    RCP<Zoltan2::CoordinateModel<ctm_base_adapter_t> > coordinateModel_ ;

    RCP<const Teuchos::Comm<int> > rcp_comm = comm_;
    RCP<const Teuchos::Comm<int> > ia_comm = rcp_comm;
    if (!is_input_adapter_distributed){
      ia_comm =  Teuchos::createSerialComm<int>();
    }

    RCP<const Environment> envConst_ = envConst;

    RCP<const ctm_base_adapter_t> baseInputAdapter_ (
        rcp(dynamic_cast<const ctm_base_adapter_t *>(input_adapter_.getRawPtr()), false));

    modelFlag_t coordFlags_, graphFlags_;

    //create coordinate model
    //since this is coordinate task mapper,
    //the adapter has to have the coordinates
    coordinateModel_ = rcp(new CoordinateModel<ctm_base_adapter_t>(
          baseInputAdapter_, envConst_, ia_comm, coordFlags_));

    //if the adapter has also graph model, we will use graph model
    //to calculate the cost mapping.
    BaseAdapterType inputType_ = input_adapter_->adapterType();
    if (inputType_ == MatrixAdapterType || 
        inputType_ == GraphAdapterType || 
        inputType_ == MeshAdapterType)
    {
      graph_model_ = rcp(new GraphModel<ctm_base_adapter_t>(
          baseInputAdapter_, envConst_, ia_comm,
            graphFlags_));
    }

    if (!machine_->hasMachineCoordinates()) {
      throw std::runtime_error("Existing machine does not provide coordinates "
                               "for coordinate task mapping");
    }

    //if mapping type is 0 then it is coordinate mapping
    int procDim = machine_->getMachineDim();
    this->nprocs = machine_->getNumRanks();

    //get processor coordinates.
    pcoord_t **procCoordinates = NULL;
    if (!machine_->getAllMachineCoordinatesView(procCoordinates)) {
      throw std::runtime_error("Existing machine does not implement "
                               "getAllMachineCoordinatesView");
    }

    //get the machine extent.
    //if we have machine extent,
    //if the machine has wrap-around links, we would like to shift the coordinates,
    //so that the largest hap would be the wrap-around.
    std::vector <int> machine_extent_vec (procDim);
    //std::vector <bool> machine_extent_wrap_around_vec(procDim, 0);
    int *machine_extent = &(machine_extent_vec[0]);
    bool *machine_extent_wrap_around = new bool[procDim];
    for (int i = 0; i < procDim; ++i)machine_extent_wrap_around[i] = false;
    machine_->getMachineExtentWrapArounds(machine_extent_wrap_around);



    // KDDKDD ASK MEHMET:  SHOULD WE GET AND USE machine_dimension HERE IF IT
    // KDDKDD ASK MEHMET:  IS PROVIDED BY THE MACHINE REPRESENTATION?
    // KDDKDD ASK MEHMET:  IF NOT HERE, THEN WHERE?
    // MD: Yes, I ADDED BELOW:
    if (machine_->getMachineExtent(machine_extent)) {
      procCoordinates =
          this->shiftMachineCoordinates (
              procDim,
              machine_extent,
              machine_extent_wrap_around,
              this->nprocs,
              procCoordinates);
    }


    //get the tasks information, such as coordinate dimension,
    //number of parts.
    int coordDim = coordinateModel_->getCoordinateDim();


    this->ntasks = soln_->getActualGlobalNumberOfParts();
    if (part_t (soln_->getTargetGlobalNumberOfParts()) > this->ntasks){
      this->ntasks = soln_->getTargetGlobalNumberOfParts();
    }
    this->solution_parts = soln_->getPartListView();

    //we need to calculate the center of parts.
    tcoord_t **partCenters = NULL;
    partCenters = allocMemory<tcoord_t *>(coordDim);
    for (int i = 0; i < coordDim; ++i){
      partCenters[i] = allocMemory<tcoord_t>(this->ntasks);
    }

    typedef typename Adapter::scalar_t t_scalar_t;


    envConst->timerStart(MACRO_TIMERS, "Mapping - Solution Center");

    //get centers for the parts.
    getSolutionCenterCoordinates<Adapter, t_scalar_t,part_t>(
        envConst.getRawPtr(),
        ia_comm.getRawPtr(),
        coordinateModel_.getRawPtr(),
        this->solution_parts,
        //soln_->getPartListView();
        //this->soln.getRawPtr(),
        coordDim,
        ntasks,
        partCenters);

    envConst->timerStop(MACRO_TIMERS, "Mapping - Solution Center");


    //create the part graph
    if (graph_model_.getRawPtr() != NULL){
      getCoarsenedPartGraph<Adapter, t_scalar_t, part_t> (
          envConst.getRawPtr(),
          ia_comm.getRawPtr(),
          graph_model_.getRawPtr(),
          this->ntasks,
          this->solution_parts,
          //soln_->getPartListView(),
          //this->soln.getRawPtr(),
          task_communication_xadj,
          task_communication_adj,
          task_communication_edge_weight
      );
    }

    //create coordinate communication model.
    this->proc_task_comm =
        new Zoltan2::CoordinateCommunicationModel<pcoord_t,tcoord_t,part_t>(
            procDim,
            procCoordinates,
            coordDim,
            partCenters,
            this->nprocs,
            this->ntasks,
            machine_extent,
            machine_extent_wrap_around,
            machine_.getRawPtr());

    int myRank = comm_->getRank();
    this->proc_task_comm->num_ranks_per_node = num_ranks_per_node ;
    this->proc_task_comm->divide_to_prime_first = divide_to_prime_first;


    envConst->timerStart(MACRO_TIMERS, "Mapping - Processor Task map");
    this->doMapping(myRank, comm_);
    envConst->timerStop(MACRO_TIMERS, "Mapping - Processor Task map");


    envConst->timerStart(MACRO_TIMERS, "Mapping - Communication Graph");

    /*soln_->getCommunicationGraph(task_communication_xadj,
               task_communication_adj);
     */

    envConst->timerStop(MACRO_TIMERS, "Mapping - Communication Graph");
  #ifdef gnuPlot1
    if (comm_->getRank() == 0){

      part_t taskCommCount = task_communication_xadj.size();
      std::cout << " TotalComm:" << task_communication_xadj[taskCommCount] << std::endl;
      part_t maxN = task_communication_xadj[0];
      for (part_t i = 1; i <= taskCommCount; ++i){
        part_t nc = task_communication_xadj[i] - task_communication_xadj[i-1];
        if (maxN < nc) maxN = nc;
      }
      std::cout << " maxNeighbor:" << maxN << std::endl;
    }

    this->writeGnuPlot(comm_, soln_, coordDim, partCenters);
  #endif

    envConst->timerStart(MACRO_TIMERS, "Mapping - Communication Cost");

    if (reduce_best_mapping && task_communication_xadj.getRawPtr() && task_communication_adj.getRawPtr()){
      this->proc_task_comm->calculateCommunicationCost(
          task_to_proc.getRawPtr(),
          task_communication_xadj.getRawPtr(),
          task_communication_adj.getRawPtr(),
          task_communication_edge_weight.getRawPtr()
      );
    }

    //std::cout << "me: " << comm_->getRank() << " cost:" << this->proc_task_comm->getCommunicationCostMetric() << std::endl;

    envConst->timerStop(MACRO_TIMERS, "Mapping - Communication Cost");

    //processors are divided into groups of size procDim! * coordDim!
    //each processor in the group obtains a mapping with a different rotation
    //and best one is broadcasted all processors.
    this->getBestMapping();
    this->create_local_task_to_rank(
        coordinateModel_->getLocalNumCoordinates(),
        this->solution_parts,
        this->task_to_proc);
    /*
    {
      if (task_communication_xadj.getRawPtr() && task_communication_adj.getRawPtr())
        this->proc_task_comm->calculateCommunicationCost(
            task_to_proc.getRawPtr(),
            task_communication_xadj.getRawPtr(),
            task_communication_adj.getRawPtr(),
            task_communication_edge_weight.getRawPtr()
        );
      std::cout << "me: " << comm_->getRank() << " cost:" << this->proc_task_comm->getCommunicationCostMetric() << std::endl;
    }
    */


  #ifdef gnuPlot
    this->writeMapping2(comm_->getRank());
  #endif

    delete []machine_extent_wrap_around;
    if (machine_->getMachineExtent(machine_extent)){
      for (int i = 0; i < procDim; ++i){
        delete [] procCoordinates[i];
      }
      delete [] procCoordinates;
    }

    for (int i = 0; i < coordDim; ++i){
      freeArray<tcoord_t>(partCenters[i]);
    }
    freeArray<tcoord_t *>(partCenters);

  }


  CoordinateTaskMapper(
      const Teuchos::RCP <const Teuchos::Comm<int> > comm_,
      const Teuchos::RCP <const MachineRepresentation<pcoord_t,part_t> > machine_,
      const Teuchos::RCP <const Adapter> input_adapter_,
      const part_t num_parts_,
      const part_t *result_parts,
      const Teuchos::RCP <const Environment> envConst,
      bool is_input_adapter_distributed = true,
      int num_ranks_per_node = 1,
      bool divide_to_prime_first = false, bool reduce_best_mapping = true):
        PartitionMapping<Adapter> (comm_, machine_, input_adapter_, num_parts_, result_parts, envConst),
        proc_to_task_xadj(0),
        proc_to_task_adj(0),
        task_to_proc(0),
        isOwnerofModel(true),
        proc_task_comm(0),
        task_communication_xadj(0),
        task_communication_adj(0),
        task_communication_edge_weight(0){
    using namespace Teuchos;
    typedef typename Adapter::base_adapter_t ctm_base_adapter_t;

    RCP<Zoltan2::GraphModel<ctm_base_adapter_t> > graph_model_;
    RCP<Zoltan2::CoordinateModel<ctm_base_adapter_t> > coordinateModel_ ;

    RCP<const Teuchos::Comm<int> > rcp_comm = comm_;
    RCP<const Teuchos::Comm<int> > ia_comm = rcp_comm;
    if (!is_input_adapter_distributed){
      ia_comm =  Teuchos::createSerialComm<int>();
    }
    RCP<const Environment> envConst_ = envConst;

    RCP<const ctm_base_adapter_t> baseInputAdapter_ (
        rcp(dynamic_cast<const ctm_base_adapter_t *>(input_adapter_.getRawPtr()), false));

    modelFlag_t coordFlags_, graphFlags_;

    //create coordinate model
    //since this is coordinate task mapper,
    //the adapter has to have the coordinates
    coordinateModel_ = rcp(new CoordinateModel<ctm_base_adapter_t>(
          baseInputAdapter_, envConst_, ia_comm, coordFlags_));

    //if the adapter has also graph model, we will use graph model
    //to calculate the cost mapping.
    BaseAdapterType inputType_ = input_adapter_->adapterType();
    if (inputType_ == MatrixAdapterType ||
        inputType_ == GraphAdapterType ||
        inputType_ == MeshAdapterType)
    {
      graph_model_ = rcp(new GraphModel<ctm_base_adapter_t>(
          baseInputAdapter_, envConst_, ia_comm,
            graphFlags_));
    }

    if (!machine_->hasMachineCoordinates()) {
      throw std::runtime_error("Existing machine does not provide coordinates "
                               "for coordinate task mapping");
    }

    //if mapping type is 0 then it is coordinate mapping
    int procDim = machine_->getMachineDim();
    this->nprocs = machine_->getNumRanks();

    //get processor coordinates.
    pcoord_t **procCoordinates = NULL;
    if (!machine_->getAllMachineCoordinatesView(procCoordinates)) {
      throw std::runtime_error("Existing machine does not implement "
                               "getAllMachineCoordinatesView");
    }

    //get the machine extent.
    //if we have machine extent,
    //if the machine has wrap-around links, we would like to shift the coordinates,
    //so that the largest hap would be the wrap-around.
    std::vector <int> machine_extent_vec (procDim);
    //std::vector <bool> machine_extent_wrap_around_vec(procDim, 0);
    int *machine_extent = &(machine_extent_vec[0]);
    bool *machine_extent_wrap_around = new bool[procDim];
    machine_->getMachineExtentWrapArounds(machine_extent_wrap_around);



    // KDDKDD ASK MEHMET:  SHOULD WE GET AND USE machine_dimension HERE IF IT
    // KDDKDD ASK MEHMET:  IS PROVIDED BY THE MACHINE REPRESENTATION?
    // KDDKDD ASK MEHMET:  IF NOT HERE, THEN WHERE?
    // MD: Yes, I ADDED BELOW:
    if (machine_->getMachineExtent(machine_extent)) {
      procCoordinates =
          this->shiftMachineCoordinates (
              procDim,
              machine_extent,
              machine_extent_wrap_around,
              this->nprocs,
              procCoordinates);
    }


    //get the tasks information, such as coordinate dimension,
    //number of parts.
    int coordDim = coordinateModel_->getCoordinateDim();


    this->ntasks = num_parts_;
    this->solution_parts = result_parts;

    //we need to calculate the center of parts.
    tcoord_t **partCenters = NULL;
    partCenters = allocMemory<tcoord_t *>(coordDim);
    for (int i = 0; i < coordDim; ++i){
      partCenters[i] = allocMemory<tcoord_t>(this->ntasks);
    }

    typedef typename Adapter::scalar_t t_scalar_t;


    envConst->timerStart(MACRO_TIMERS, "Mapping - Solution Center");

    //get centers for the parts.
    getSolutionCenterCoordinates<Adapter, t_scalar_t,part_t>(
        envConst.getRawPtr(),
        ia_comm.getRawPtr(),
        coordinateModel_.getRawPtr(),
        this->solution_parts,
        //soln_->getPartListView();
        //this->soln.getRawPtr(),
        coordDim,
        ntasks,
        partCenters);

    envConst->timerStop(MACRO_TIMERS, "Mapping - Solution Center");

    envConst->timerStart(MACRO_TIMERS, "GRAPHCREATE");
    //create the part graph
    if (graph_model_.getRawPtr() != NULL){
      getCoarsenedPartGraph<Adapter, t_scalar_t, part_t> (
          envConst.getRawPtr(),
          ia_comm.getRawPtr(),
          graph_model_.getRawPtr(),
          this->ntasks,
          this->solution_parts,
          //soln_->getPartListView(),
          //this->soln.getRawPtr(),
          task_communication_xadj,
          task_communication_adj,
          task_communication_edge_weight
      );
    }
    envConst->timerStop(MACRO_TIMERS, "GRAPHCREATE");


    envConst->timerStart(MACRO_TIMERS, "CoordinateCommunicationModel Create");
    //create coordinate communication model.
    this->proc_task_comm =
        new Zoltan2::CoordinateCommunicationModel<pcoord_t,tcoord_t,part_t>(
            procDim,
            procCoordinates,
            coordDim,
            partCenters,
            this->nprocs,
            this->ntasks,
            machine_extent,
            machine_extent_wrap_around,
            machine_.getRawPtr());

    envConst->timerStop(MACRO_TIMERS, "CoordinateCommunicationModel Create");


    this->proc_task_comm->num_ranks_per_node = num_ranks_per_node;
    this->proc_task_comm->divide_to_prime_first = divide_to_prime_first;

    int myRank = comm_->getRank();


    envConst->timerStart(MACRO_TIMERS, "Mapping - Processor Task map");
    this->doMapping(myRank, comm_);
    envConst->timerStop(MACRO_TIMERS, "Mapping - Processor Task map");


    envConst->timerStart(MACRO_TIMERS, "Mapping - Communication Graph");

    /*soln_->getCommunicationGraph(task_communication_xadj,
               task_communication_adj);
     */

    envConst->timerStop(MACRO_TIMERS, "Mapping - Communication Graph");
  #ifdef gnuPlot1
    if (comm_->getRank() == 0){

      part_t taskCommCount = task_communication_xadj.size();
      std::cout << " TotalComm:" << task_communication_xadj[taskCommCount] << std::endl;
      part_t maxN = task_communication_xadj[0];
      for (part_t i = 1; i <= taskCommCount; ++i){
        part_t nc = task_communication_xadj[i] - task_communication_xadj[i-1];
        if (maxN < nc) maxN = nc;
      }
      std::cout << " maxNeighbor:" << maxN << std::endl;
    }

    this->writeGnuPlot(comm_, soln_, coordDim, partCenters);
  #endif

    envConst->timerStart(MACRO_TIMERS, "Mapping - Communication Cost");

    if (reduce_best_mapping && task_communication_xadj.getRawPtr() && task_communication_adj.getRawPtr()){
      this->proc_task_comm->calculateCommunicationCost(
          task_to_proc.getRawPtr(),
          task_communication_xadj.getRawPtr(),
          task_communication_adj.getRawPtr(),
          task_communication_edge_weight.getRawPtr()
      );
    }

    //std::cout << "me: " << comm_->getRank() << " cost:" << this->proc_task_comm->getCommunicationCostMetric() << std::endl;

    envConst->timerStop(MACRO_TIMERS, "Mapping - Communication Cost");

    //processors are divided into groups of size procDim! * coordDim!
    //each processor in the group obtains a mapping with a different rotation
    //and best one is broadcasted all processors.
    this->getBestMapping();

    this->create_local_task_to_rank(
         coordinateModel_->getLocalNumCoordinates(),
         this->solution_parts,
         this->task_to_proc);
    /*

    {
      if (task_communication_xadj.getRawPtr() && task_communication_adj.getRawPtr())
        this->proc_task_comm->calculateCommunicationCost(
            task_to_proc.getRawPtr(),
            task_communication_xadj.getRawPtr(),
            task_communication_adj.getRawPtr(),
            task_communication_edge_weight.getRawPtr()
        );
      std::cout << "me: " << comm_->getRank() << " cost:" << this->proc_task_comm->getCommunicationCostMetric() << std::endl;
    }
    */



  #ifdef gnuPlot
    this->writeMapping2(comm_->getRank());
  #endif

    delete []machine_extent_wrap_around;
    if (machine_->getMachineExtent(machine_extent)){
      for (int i = 0; i < procDim; ++i){
        delete [] procCoordinates[i];
      }
      delete [] procCoordinates;
    }

    for (int i = 0; i < coordDim; ++i){
      freeArray<tcoord_t>(partCenters[i]);
    }
    freeArray<tcoord_t *>(partCenters);

  }

  CoordinateTaskMapper(
      const Environment *env_const_,
      const Teuchos::Comm<int> *problemComm,
      int proc_dim,
      int num_processors,
      pcoord_t **machine_coords,

      int task_dim,
      part_t num_tasks,
      tcoord_t **task_coords,
      ArrayRCP<part_t>task_comm_xadj,
      ArrayRCP<part_t>task_comm_adj,
      pcoord_t *task_communication_edge_weight_,
      int recursion_depth,
      part_t *part_no_array,
      const part_t *machine_dimensions,
      int num_ranks_per_node = 1,
      bool divide_to_prime_first = false, bool reduce_best_mapping = true
  ):  PartitionMapping<Adapter>(
      Teuchos::rcpFromRef<const Teuchos::Comm<int> >(*problemComm),
      Teuchos::rcpFromRef<const Environment> (*env_const_)),
      proc_to_task_xadj(0),
      proc_to_task_adj(0),
      task_to_proc(0),
      isOwnerofModel(true),
      proc_task_comm(0),
      task_communication_xadj(task_comm_xadj),
      task_communication_adj(task_comm_adj){

    //if mapping type is 0 then it is coordinate mapping
    pcoord_t ** virtual_machine_coordinates  = machine_coords;
    bool *wrap_arounds = new bool [proc_dim];
    for (int i = 0; i < proc_dim; ++i) wrap_arounds[i] = true;

    if (machine_dimensions){
      virtual_machine_coordinates =
          this->shiftMachineCoordinates (
              proc_dim,
              machine_dimensions,
              wrap_arounds,
              num_processors,
              machine_coords);
    }

    this->nprocs = num_processors;

    int coordDim = task_dim;
    this->ntasks = num_tasks;

    //alloc memory for part centers.
    tcoord_t **partCenters = task_coords;

    //create coordinate communication model.
    this->proc_task_comm =
        new Zoltan2::CoordinateCommunicationModel<pcoord_t,tcoord_t,part_t>(
            proc_dim,
            virtual_machine_coordinates,
            coordDim,
            partCenters,
            this->nprocs,
            this->ntasks, NULL, NULL
        );

    this->proc_task_comm->num_ranks_per_node = num_ranks_per_node;
    this->proc_task_comm->divide_to_prime_first = divide_to_prime_first;

    this->proc_task_comm->setPartArraySize(recursion_depth);
    this->proc_task_comm->setPartArray(part_no_array);

    int myRank = problemComm->getRank();

    this->doMapping(myRank, this->comm);
#ifdef gnuPlot
    this->writeMapping2(myRank);
#endif

    if (reduce_best_mapping && task_communication_xadj.getRawPtr() && task_communication_adj.getRawPtr()){
      this->proc_task_comm->calculateCommunicationCost(
          task_to_proc.getRawPtr(),
          task_communication_xadj.getRawPtr(),
          task_communication_adj.getRawPtr(),
          task_communication_edge_weight_
      );


      this->getBestMapping();

/*
      if (myRank == 0){
        this->proc_task_comm->calculateCommunicationCost(
            task_to_proc.getRawPtr(),
            task_communication_xadj.getRawPtr(),
            task_communication_adj.getRawPtr(),
            task_communication_edge_weight_
        );
        cout << "me: " << problemComm->getRank() << " cost:" << this->proc_task_comm->getCommunicationCostMetric() << endl;
      }
*/

    }
    delete [] wrap_arounds;

    if (machine_dimensions){
      for (int i = 0; i < proc_dim; ++i){
        delete [] virtual_machine_coordinates[i];
      }
      delete [] virtual_machine_coordinates;
    }
#ifdef gnuPlot
    if(problemComm->getRank() == 0)
      this->writeMapping2(-1);
#endif
  }


  /*
  double getCommunicationCostMetric(){
    return this->proc_task_comm->getCommCost();
  }
  */

  virtual size_t getLocalNumberOfParts() const{
    return 0;
  }

  pcoord_t **shiftMachineCoordinates(
      int machine_dim,
      const part_t *machine_dimensions,
      bool *machine_extent_wrap_around,
      part_t numProcs,
      pcoord_t **mCoords){
    pcoord_t **result_machine_coords = NULL;
    result_machine_coords = new pcoord_t*[machine_dim];
    for (int i = 0; i < machine_dim; ++i){
      result_machine_coords[i] = new pcoord_t [numProcs];
    }

    for (int i = 0; i < machine_dim; ++i){
      part_t numMachinesAlongDim = machine_dimensions[i];
      part_t *machineCounts= new part_t[numMachinesAlongDim];
      memset(machineCounts, 0, sizeof(part_t) *numMachinesAlongDim);

      int *filledCoordinates= new int[numMachinesAlongDim];

      pcoord_t *coords = mCoords[i];
      for(part_t j = 0; j < numProcs; ++j){
        part_t mc = (part_t) coords[j];
        ++machineCounts[mc];
      }

      part_t filledCoordinateCount = 0;
      for(part_t j = 0; j < numMachinesAlongDim; ++j){
        if (machineCounts[j] > 0){
          filledCoordinates[filledCoordinateCount++] = j;
        }
      }

      part_t firstProcCoord = filledCoordinates[0];
      part_t firstProcCount = machineCounts[firstProcCoord];

      part_t lastProcCoord = filledCoordinates[filledCoordinateCount - 1];
      part_t lastProcCount = machineCounts[lastProcCoord];

      part_t firstLastGap = numMachinesAlongDim - lastProcCoord + firstProcCoord;
      part_t firstLastGapProc = lastProcCount + firstProcCount;

      part_t leftSideProcCoord = firstProcCoord;
      part_t leftSideProcCount = firstProcCount;
      part_t biggestGap = 0;
      part_t biggestGapProc = numProcs;

      part_t shiftBorderCoordinate = -1;
      for(part_t j = 1; j < filledCoordinateCount; ++j){
        part_t rightSideProcCoord= filledCoordinates[j];
        part_t rightSideProcCount = machineCounts[rightSideProcCoord];

        part_t gap = rightSideProcCoord - leftSideProcCoord;
        part_t gapProc = rightSideProcCount + leftSideProcCount;

        /* Pick the largest gap in this dimension. Use fewer process on either side
           of the largest gap to break the tie. An easy addition to this would
           be to weight the gap by the number of processes. */
        if (gap > biggestGap || (gap == biggestGap && biggestGapProc > gapProc)){
          shiftBorderCoordinate = rightSideProcCoord;
          biggestGapProc = gapProc;
          biggestGap = gap;
        }
        leftSideProcCoord = rightSideProcCoord;
        leftSideProcCount = rightSideProcCount;
      }


      if (!(biggestGap > firstLastGap || (biggestGap == firstLastGap && biggestGapProc < firstLastGapProc))){
        shiftBorderCoordinate = -1;
      }

      for(part_t j = 0; j < numProcs; ++j){

        if (machine_extent_wrap_around[i] && coords[j] < shiftBorderCoordinate){
          result_machine_coords[i][j] = coords[j] + numMachinesAlongDim;

        }
        else {
          result_machine_coords[i][j] = coords[j];
        }
        //cout << "I:" << i << "j:" << j << " coord:" << coords[j] << " now:" << result_machine_coords[i][j] << endl;
      }
      delete [] machineCounts;
      delete [] filledCoordinates;
    }

    return result_machine_coords;

  }

  virtual void getProcsForPart(part_t taskId, part_t &numProcs, part_t *&procs) const{
    numProcs = 1;
    procs = this->task_to_proc.getRawPtr() + taskId;
  }
  inline part_t getAssignedProcForTask(part_t taskId){
    return this->task_to_proc[taskId];
  }
  virtual void getPartsForProc(int procId, part_t &numParts, part_t *&parts) const{

    part_t task_begin = this->proc_to_task_xadj[procId];
    part_t taskend = this->proc_to_task_xadj[procId+1];
    parts = this->proc_to_task_adj.getRawPtr() + task_begin;
    numParts = taskend - task_begin;
  }

  ArrayView<part_t> getAssignedTasksForProc(part_t procId){
    part_t task_begin = this->proc_to_task_xadj[procId];
    part_t taskend = this->proc_to_task_xadj[procId+1];

    /*
  cout << "part_t:" << procId << " taskCount:" << taskend - task_begin << endl;
  for(part_t i = task_begin; i < taskend; ++i){
      cout << "part_t:" << procId << " task:" << proc_to_task_adj[i] << endl;
  }
     */
    if (taskend - task_begin > 0){
      ArrayView <part_t> assignedParts(this->proc_to_task_adj.getRawPtr() + task_begin, taskend - task_begin);
      return assignedParts;
    }
    else {
      ArrayView <part_t> assignedParts;
      return assignedParts;
    }
  }

};



template <typename part_t, typename pcoord_t, typename tcoord_t>
void coordinateTaskMapperInterface(
    RCP<const Teuchos::Comm<int> > problemComm,
    int proc_dim,
    int num_processors,
    pcoord_t **machine_coords,
    int task_dim,
    part_t num_tasks,
    tcoord_t **task_coords,
    part_t *task_comm_xadj,
    part_t *task_comm_adj,
    pcoord_t *task_communication_edge_weight_, /*float-like, same size with task_communication_adj_ weight of the corresponding edge.*/
    part_t *proc_to_task_xadj, /*output*/
    part_t *proc_to_task_adj, /*output*/
    int recursion_depth,
    part_t *part_no_array,
    const part_t *machine_dimensions,
    int num_ranks_per_node = 1,
    bool divide_to_prime_first = false
)
{

  const Environment *envConst_ = new Environment(problemComm);

  // mfh 03 Mar 2015: It's OK to omit the Node template
  // parameter in Tpetra, if you're just going to use the
  // default Node.
  typedef Tpetra::MultiVector<tcoord_t, part_t, part_t> tMVector_t;

  Teuchos::ArrayRCP<part_t> task_communication_xadj (task_comm_xadj, 0, num_tasks+1, false);

  Teuchos::ArrayRCP<part_t> task_communication_adj;
  if (task_comm_xadj){
    Teuchos::ArrayRCP<part_t> tmp_task_communication_adj (task_comm_adj, 0, task_comm_xadj[num_tasks], false);
    task_communication_adj = tmp_task_communication_adj;
  }


  CoordinateTaskMapper<XpetraMultiVectorAdapter <tMVector_t>, part_t> *ctm =
      new CoordinateTaskMapper<XpetraMultiVectorAdapter <tMVector_t>, part_t>(
      envConst_,
      problemComm.getRawPtr(),
      proc_dim,
      num_processors,
      machine_coords,//machine_coords_,

      task_dim,
      num_tasks,
      task_coords,

      task_communication_xadj,
      task_communication_adj,
      task_communication_edge_weight_,
      recursion_depth,
      part_no_array,
      machine_dimensions,
      num_ranks_per_node,
      divide_to_prime_first
  );


  part_t* proc_to_task_xadj_;
  part_t* proc_to_task_adj_;

  ctm->getProcTask(proc_to_task_xadj_, proc_to_task_adj_);

  for (part_t i = 0; i <= num_processors; ++i){
    proc_to_task_xadj[i] = proc_to_task_xadj_[i];
  }
  for (part_t i = 0; i < num_tasks; ++i){
    proc_to_task_adj[i] = proc_to_task_adj_[i];
  }
  delete ctm;
  delete envConst_;

}

template <typename proc_coord_t, typename v_lno_t>
inline void visualize_mapping(int myRank,
    const int machine_coord_dim, const int num_ranks, proc_coord_t **machine_coords,
    const v_lno_t num_tasks, const v_lno_t *task_communication_xadj, const v_lno_t *task_communication_adj, const int *task_to_rank){

  std::string rankStr = Teuchos::toString<int>(myRank);
  std::string gnuPlots = "gnuPlot", extentionS = ".plot";
  std::string outF = gnuPlots + rankStr+ extentionS;
  std::ofstream gnuPlotCode ( outF.c_str(), std::ofstream::out);

  if (machine_coord_dim != 3) {
    std::cerr << "Mapping Write is only good for 3 dim" << std::endl;
    return;
  }
  std::string ss = "";
  std::string procs = "";

  std::set < std::tuple<int,int,int,int,int,int> > my_arrows;
  for(v_lno_t origin_task = 0; origin_task < num_tasks; ++origin_task){
    int origin_rank = task_to_rank[origin_task];
    std::string gnuPlotArrow = "set arrow from ";

    for(int j = 0; j <  machine_coord_dim; ++j){
      if (j == machine_coord_dim - 1){
        gnuPlotArrow += Teuchos::toString<proc_coord_t>(machine_coords[j][origin_rank]);
        procs += Teuchos::toString<proc_coord_t>(machine_coords[j][origin_rank]);

      }
      else {
        gnuPlotArrow += Teuchos::toString<proc_coord_t>(machine_coords[j][origin_rank]) +",";
        procs += Teuchos::toString<proc_coord_t>(machine_coords[j][origin_rank])+ " ";
      }
    }
    procs += "\n";

    gnuPlotArrow += " to ";


    for (int nind = task_communication_xadj[origin_task]; nind < task_communication_xadj[origin_task + 1]; ++nind){
      int neighbor_task = task_communication_adj[nind];

      bool differentnode = false;
      int neighbor_rank = task_to_rank[neighbor_task];

      for(int j = 0; j <  machine_coord_dim; ++j){
        if (int (machine_coords[j][origin_rank]) != int (machine_coords[j][neighbor_rank])){
          differentnode = true; break;
        }
      }
      std::tuple<int,int,int, int, int, int> foo (
          (int) (machine_coords[0][origin_rank]),
          (int)  (machine_coords[1][origin_rank]),
          (int) (machine_coords[2][origin_rank]),
          (int) (machine_coords[0][neighbor_rank]),
          (int) (machine_coords[1][neighbor_rank]),
          (int) (machine_coords[2][neighbor_rank]));


      if (differentnode && my_arrows.find(foo) == my_arrows.end()){
        my_arrows.insert(foo);

        std::string gnuPlotArrow2 = "";
        for(int j = 0; j <  machine_coord_dim; ++j){
          if(j == machine_coord_dim - 1){
            gnuPlotArrow2 += Teuchos::toString<float>(machine_coords[j][neighbor_rank]);
          }
          else{
            gnuPlotArrow2 += Teuchos::toString<float>(machine_coords[j][neighbor_rank]) +",";
          }
        }
        ss += gnuPlotArrow + gnuPlotArrow2 + " nohead\n";
      }
    }
  }

  std::ofstream procFile ("procPlot.plot", std::ofstream::out);
  procFile << procs << "\n";
  procFile.close();

  //gnuPlotCode << ss;
  if(machine_coord_dim == 2){
    gnuPlotCode << "plot \"procPlot.plot\" with points pointsize 3\n";
  } else {
    gnuPlotCode << "splot \"procPlot.plot\" with points pointsize 3\n";
  }

  gnuPlotCode << ss << "\nreplot\n pause -1\npause -1";
  gnuPlotCode.close();
}

}// namespace Zoltan2

#endif