static char help[] = "Load data into subvector.\n\n";

#include <petscvec.h>
#include <petscviewerhdf5.h>

int main(int argc,char **argv)
{
  Vec            testvec, loadvec;
  IS             loadis;
  PetscMPIInt    size,rank;
  PetscInt       low,high;
  PetscInt       issize, isstart;
  PetscInt       skipuntil = 50;
  PetscViewer    hdf5_viewer;
  PetscErrorCode ierr;

  PetscFunctionBegin;

  ierr = PetscInitialize(&argc, &argv, (char*) 0, help);if (ierr) return ierr;
  ierr = MPI_Comm_size(PETSC_COMM_WORLD, &size);CHKERRQ(ierr);
  ierr = MPI_Comm_rank(PETSC_COMM_WORLD, &rank);CHKERRQ(ierr);

  ierr = VecCreate(PETSC_COMM_WORLD, &testvec);CHKERRQ(ierr);
  ierr = VecSetSizes(testvec, PETSC_DECIDE,100);CHKERRQ(ierr);
  ierr = VecSetUp(testvec);CHKERRQ(ierr);
  ierr = VecSet(testvec, (PetscScalar) 1);CHKERRQ(ierr);

  ierr = VecGetOwnershipRange(testvec, &low, &high);CHKERRQ(ierr);
  if( low>=skipuntil ) {
    isstart = low;
    issize = high - low;
  } else if( low<=skipuntil && high>=skipuntil ) {
    isstart = skipuntil;
    issize = high - skipuntil;
  } else {
    isstart = low;
    issize  = 0;
  }
  ierr = ISCreateStride(PETSC_COMM_WORLD, issize, isstart, 1, &loadis);CHKERRQ(ierr);

  PetscPrintf(PETSC_COMM_SELF,"Vec-Ownership : %d to %d, index set size & start : %d : %d \n", low, high, issize, isstart);

  ierr = VecGetSubVector(testvec, loadis, &loadvec);CHKERRQ(ierr);
  ierr = PetscObjectSetName((PetscObject)loadvec,"test"); CHKERRQ(ierr);
  ierr = PetscViewerHDF5Open(PETSC_COMM_WORLD,"testinput.h5",
      FILE_MODE_READ,&hdf5_viewer); CHKERRQ(ierr);

  ierr = VecLoad(loadvec, hdf5_viewer);CHKERRQ(ierr);

  ierr = PetscViewerHDF5Open(PETSC_COMM_WORLD,"testsubload.h5",
      FILE_MODE_WRITE,&hdf5_viewer);CHKERRQ(ierr);
  ierr = VecView(loadvec,hdf5_viewer);CHKERRQ(ierr);
  ierr = PetscViewerDestroy(&hdf5_viewer);CHKERRQ(ierr);

  ierr = VecRestoreSubVector(testvec, loadis, &loadvec);CHKERRQ(ierr);
  ierr = VecDestroy(&loadvec); CHKERRQ(ierr);

  ierr = PetscObjectSetName((PetscObject)testvec,"testvec"); CHKERRQ(ierr);
  ierr = PetscViewerHDF5Open(PETSC_COMM_WORLD,"testload.h5",
      FILE_MODE_WRITE,&hdf5_viewer);CHKERRQ(ierr);
  ierr = VecView(testvec,hdf5_viewer);CHKERRQ(ierr);
  ierr = PetscViewerDestroy(&hdf5_viewer);CHKERRQ(ierr);

  ierr = VecDestroy(&testvec); CHKERRQ(ierr);
  ierr = PetscFinalize();
  return ierr;
}