Method MultAdd

parallel/parallel_matrices.cpp:278–357

  template <typename TM>
  void MasterInverse<TM> :: MultAdd (double s, const BaseVector & x, BaseVector & y) const
  {
    typedef typename mat_traits<TM>::TV_ROW TV;
    
    NgMPI_Comm comm = paralleldofs->GetCommunicator();
    int id = comm.Rank();
    int ntasks = comm.Size();

    bool is_x_cum = (dynamic_cast_ParallelBaseVector(x) . Status() == CUMULATED);
    // x.Distribute();
    y.Cumulate();

    if (id > 0)
      {
	FlatVector<TV> fx = x.FV<TV> ();
	FlatVector<TV> fy = y.FV<TV> ();

	Array<TV> lx (select.Size());
	for (int i = 0; i < select.Size(); i++)
	  lx[i] = fx(select[i]);

	NgMPI_Request(comm.ISend (lx, 0, NG_MPI_TAG_SOLVE)).Wait();

	// only for MUMPS:
	if (inv)
	  y = (*inv) * x;
	
	NgMPI_Request(comm.IRecv (lx, 0, NG_MPI_TAG_SOLVE)).Wait();

	for (int i = 0; i < select.Size(); i++)
	  fy(select[i]) += s * lx[i];
      }

    else
      {
	VVector<TV> hx(inv->Height());
	VVector<TV> hy(inv->Height());
	hx = 0.0;

	Array<int> sizes(ntasks);
	for (int i = 0; i < ntasks; i++)
	  sizes[i] = loc2glob[i].Size();

	Table<TV> exdata(sizes);


	for (int src = 1; src < ntasks; src++)
	  {
	    FlatArray<int> selecti = loc2glob[src];

	    Array<TV> lx(selecti.Size());
	    comm.Recv (lx, src, NG_MPI_TAG_SOLVE);

	    if(is_x_cum) {
	      for (int i = 0; i < selecti.Size(); i++)
		hx(selecti[i]) = lx[i];
	    }
	    else {