static char help[] = "Basic Nest vector create.\n\n";

#include <petsc.h>
#include <petscvec.h>

int main( int argc, char **args )
{
  Vec X ;
  PetscErrorCode ierr ;

  PetscInitialize( &argc, &args,(char *)0, help );

  ierr = VecCreate( PETSC_COMM_WORLD, &X );CHKERRQ(ierr);
  ierr = VecSetSizes( X, 2, 2 );CHKERRQ(ierr);
  /*ierr = VecSetType( X, VECNEST );CHKERRQ(ierr);*/
  ierr = PetscObjectChangeTypeName((PetscObject)X,VECNEST);CHKERRQ(ierr);
  ierr = VecSetFromOptions(X);

  ierr = VecView(X,0);

  ierr = VecDestroy(&X) ;

  PetscFinalize();
  return 0;
}