MPI_Send(&size, 3, MPI_INT, target, tag, MPI_COMM_WORLD);
const double *p=da->getConstPointer();
MPI_Send(const_cast<double*>(&p[0]), size[0] ,MPI_DOUBLE, target, tag+100, MPI_COMM_WORLD);
MPI_Send(&size, 3, MPI_INT, target, tag, MPI_COMM_WORLD);
const double *p=da->getConstPointer();
MPI_Send(const_cast<double*>(&p[0]), size[0] ,MPI_DOUBLE, target, tag+100, MPI_COMM_WORLD);