static char help[] = "Test using MatPreallocator to preallocate two matrices\n\n";

/*T
   Concepts: Mat^matrix preallocation
   Processors: n
T*/

#include <petscmat.h>

PetscErrorCode ex1_nonsquare_bs1(void)
{
  Mat            A,A_duplicate,preallocator;
  PetscInt       M,N,m,n,bs;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  M = 10;
  N = 8;
  ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
  ierr = MatSetType(A,MATAIJ);CHKERRQ(ierr);
  ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,M,N);CHKERRQ(ierr);
  ierr = MatSetBlockSize(A,1);CHKERRQ(ierr);
  ierr = MatSetFromOptions(A);CHKERRQ(ierr);

  ierr = MatCreate(PETSC_COMM_WORLD,&A_duplicate);CHKERRQ(ierr);
  ierr = MatSetType(A_duplicate,MATAIJ);CHKERRQ(ierr);
  ierr = MatSetSizes(A_duplicate,PETSC_DECIDE,PETSC_DECIDE,M,N);CHKERRQ(ierr);
  ierr = MatSetBlockSize(A_duplicate,2);CHKERRQ(ierr);
  ierr = MatSetFromOptions(A_duplicate);CHKERRQ(ierr);

  ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
  ierr = MatGetBlockSize(A,&bs);CHKERRQ(ierr);

  ierr = MatCreate(PetscObjectComm((PetscObject)A),&preallocator);CHKERRQ(ierr);
  ierr = MatSetType(preallocator,MATPREALLOCATOR);CHKERRQ(ierr);
  ierr = MatSetSizes(preallocator,m,n,M,N);CHKERRQ(ierr);
  ierr = MatSetBlockSize(preallocator,bs);CHKERRQ(ierr);
  ierr = MatSetUp(preallocator);CHKERRQ(ierr);

  ierr = MatSetValue(preallocator,3,3,0,INSERT_VALUES);CHKERRQ(ierr);
  ierr = MatAssemblyBegin(preallocator,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatAssemblyEnd(preallocator,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);

  ierr = MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A);CHKERRQ(ierr);
  ierr = MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A_duplicate);CHKERRQ(ierr);

  ierr = MatDestroy(&preallocator);CHKERRQ(ierr);

  ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
  ierr = MatSetValue(A,3,3,0.3,INSERT_VALUES);CHKERRQ(ierr);
  ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
  ierr = MatDestroy(&A);CHKERRQ(ierr);

  ierr = MatView(A_duplicate,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
  ierr = MatSetValue(A_duplicate,3,3,0.3,INSERT_VALUES);CHKERRQ(ierr);
  ierr = MatAssemblyBegin(A_duplicate,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatAssemblyEnd(A_duplicate,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatView(A_duplicate,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
  ierr = MatDestroy(&A_duplicate);CHKERRQ(ierr);

  PetscFunctionReturn(0);
}

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

  ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
  ierr = ex1_nonsquare_bs1();CHKERRQ(ierr);
  ierr = PetscFinalize();
  return ierr;
}

/*TEST

   test:
     nsize: {{1 2}separate output}

TEST*/