hypre_obj_SetupMatrixIJ Subroutine

    impure subroutine hypre_obj_SetupMatrixIJ(this)
      !> Sets up matrix with IJ interface.
      implicit none
      class(hypre_obj), intent(inout) :: this                                  !! Hypre machinery
      ! Work variables
      integer :: ierr

      ! Create an empty matrix object
      call HYPRE_IJMatrixCreate(this%comm, this%irow_lo,this%irow_hi, this%irow_lo,this%irow_hi,this%matrix,ierr)

      ! Set storage type: only HYPRE_PARCSR supported per HYPRE doc
      call HYPRE_IJMatrixSetObjectType(this%matrix,HYPRE_PARCSR,ierr)

      ! Initialize before setting coefficients
      call HYPRE_IJMatrixInitialize(this%matrix,ierr)

      ! Set matrix coefficients
      call hypre_obj_BuildMatrixIJ(this)

      ! Assemble matrix
      call HYPRE_IJMatrixAssemble(this%matrix, ierr)

      ! Get parcsr matrix object
      call HYPRE_IJMatrixGetObject(this%matrix,this%par_matrix,ierr)

      return
    end subroutine hypre_obj_SetupMatrixIJ