diff_ptr_sph Subroutine

  subroutine diff_ptr_sph(grid, coordX, coordY, nx, ny, dx, dy, src, error, rc)
    type(ESMF_Grid), intent(in)      :: grid
    real(ESMF_KIND_R8), pointer      :: coordX(:,:)
    real(ESMF_KIND_R8), pointer      :: coordY(:,:)
    integer, intent(in)              :: nx, ny
    real, intent(in)                 :: dx, dy
    real(ESMF_KIND_R8), pointer      :: src(:,:), error(:,:)
    integer, intent(out), optional   :: rc

    integer                          :: localrc, i,j 

    if(present(rc)) rc = ESMF_SUCCESS

    call ESMF_GridGetCoord(grid, localDE=0, &
        staggerLoc=ESMF_STAGGERLOC_CENTER, &
        coordDim=1, farrayPtr=coordX, rc=localrc)
    if (ESMF_LogFoundError(localrc, &
        ESMF_ERR_PASSTHRU, &
        ESMF_CONTEXT, rcToReturn=rc)) return
    ! Y center 
    call ESMF_GridGetCoord(grid, localDE=0, &
        staggerLoc=ESMF_STAGGERLOC_CENTER, &
        coordDim=2, farrayPtr=coordY, rc=localrc)
    if (ESMF_LogFoundError(localrc, &
        ESMF_ERR_PASSTHRU, &
        ESMF_CONTEXT, rcToReturn=rc)) return
    do i = lbound(coordX,1), ubound(coordX,1)
      do j = lbound(coordX,2), ubound(coordX,2)
        error(i,j) = src(i,j) - error(i,j)
      enddo
    enddo

  end subroutine diff_ptr_sph