static char help[] = "Tests MatConvert from AIJ to MATIS.\n";

#include <petscmat.h>
int main(int argc,char **args)
{
  Mat            A,B;
  char           file[PETSC_MAX_PATH_LEN];
  PetscViewer    fd;
  PetscBool      flg;

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

  /* Load aij matrix A */
  PetscCall(PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg));
  PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option");
  PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd));
  PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
  PetscCall(MatLoad(A,fd));

  MatConvert(A,MATIS,MAT_INITIAL_MATRIX,&B);

  PetscCall(MatDestroy(&A));
  PetscCall(MatDestroy(&B));
  PetscCall(PetscViewerDestroy(&fd));
  PetscCall(PetscFinalize());
}