#undef __FUNCT__
#define __FUNCT__ "petsc::PETScLibTest::testMatPreallocation"
void petsc::PETScLibTest::testMatPreallocation(){
  
  _log.debug("testMatPreallocation()","start PETSc mat preallocation test");
  
  Mat matrix;
  const int rows = 4;
  const int cols = 4;
  
  int nnzCounter[rows];
  for (int i=0; i<rows; i++) {
    nnzCounter[i] = 0;
  }
  nnzCounter[0] = 2;
  nnzCounter[1] = 4;
  nnzCounter[2] = 3;
  nnzCounter[3] = 1;
  
  _ierr = MatCreateSeqAIJ(PETSC_COMM_WORLD, rows, cols, 
                            PETSC_NULL, nnzCounter, &matrix);
  PETSc_CHKERRQ(_ierr); 
  
  MatInfo info;
  _ierr = MatGetInfo(matrix,MAT_GLOBAL_SUM,&info);
  PETSc_CHKERRQ(_ierr);
  int expectedNonzerosUsed = 0;
  int expectedNonzerosAllocated = 10;
  int expectedNonzerosUnneeded = expectedNonzerosAllocated - expectedNonzerosUsed;
  validateEquals( (PetscInt)info.nz_used,      expectedNonzerosUsed,      "testMatPreallocation()");
  validateEquals( (PetscInt)info.nz_allocated, expectedNonzerosAllocated, "testMatPreallocation()");
  validateEquals( (PetscInt)info.nz_unneeded,  expectedNonzerosUnneeded,  "testMatPreallocation()");
  
  _ierr = MatAssemblyBegin(matrix,MAT_FINAL_ASSEMBLY);
  PETSc_CHKERRQ(_ierr);
  _ierr = MatAssemblyEnd(matrix,MAT_FINAL_ASSEMBLY);  
  PETSc_CHKERRQ(_ierr);
  
  
  double dummyValue = 1.5;
  int row = 0;
  int col = 0;
  _ierr = MatSetValue(matrix, row, col, dummyValue, ADD_VALUES); 
  PETSc_CHKERRQ(_ierr);
  
  _ierr = MatAssemblyBegin(matrix,MAT_FINAL_ASSEMBLY);
  PETSc_CHKERRQ(_ierr);
  _ierr = MatAssemblyEnd(matrix,MAT_FINAL_ASSEMBLY);  
  PETSc_CHKERRQ(_ierr);
  
  _log.debug("testMatPreallocation()","stop PETSc mat preallocation test");
}