anchor.diff:  ! -----------------------------------------------------------------------------
   
   subroutine read_input_fileH_2D(name,array,default,nx,ny)
  -
  -  implicit none
  +  implicit none
  +
     character(30) name
     integer nx, ny
     double precision array(0:nx+1,0:ny+1), default
  
positive.code: 
  !> Calculate the barotropic v velocity
  subroutine calc_baro_v(vb,v,h,eta,freesurfFac,nx,ny,layers)
  
    integer nx,ny,layers
    integer i,j,k
  
negative.code: subroutine evaluate_dudt(dudt, h,u,v,b,zeta,wind_x,fu, &
      au,ar,slip,dx,dy,hfacN,hfacS,nx,ny,layers,rho0, &
      spongeTimeScale,spongeU,RedGrav,botDrag)
    implicit none
  
    ! dudt(i,j) is evaluated at the centre of the left edge of the grid
    ! box, the same place as u(i,j).
    integer nx,ny,layers
  