1: #include <../src/mat/impls/aij/mpi/mpiaij.h> 3: PetscErrorCode MatGetDiagonalBlock_MPIAIJ(Mat A, Mat *a) 4: { 5: PetscFunctionBegin; 6: *a = ((Mat_MPIAIJ *)A->data)->A; 7: PetscFunctionReturn(PETSC_SUCCESS); 8: }