anchor.diff:    integer :: num_procs, myid
     integer :: ilower(0:num_procs-1,2), iupper(0:num_procs-1,2)
   
  -  if (myid .eq. 0) then
     ! Calculate the barotropic velocities
     call calc_baro_u(ub, unew, hnew, eta, freesurfFac, nx, ny, layers)
     call calc_baro_v(vb, vnew, hnew, eta, freesurfFac, nx, ny, layers)
  
positive.code:     ! them consistent.
      call enforce_depth_thickness_consistency(h, eta, depth, &
          freesurfFac, thickness_error, nx, ny, layers)
  
    end if
  
    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  
negative.code:     maxits, eps, rjac, freesurfFac, thickness_error, &
      g_vec, nx, ny, layers, n, &
       MPI_COMM_WORLD, myid, num_procs, ilower, iupper, & 
       hypre_grid, hypre_A, ierr)
       ! , &
      ! hypre_grid, hypre_A, hypre_b, hypre_x)
    implicit none
  