anchor.diff:       
               deltap = (fpfine1(jj1,mq) + fpfine1(jj2,mq)) -
        &               (eff1(jj1,mq,1) + eff1(jj2,mq,1))
  -
  +             
   c           # Put the same value in four ghost cells;  grab the first
   c           # one that shows up in the transformation.          
               do jj = jj1,jj2
  
positive.code:       integer i,j,mq
        integer i1,j1, i2, j2
  
        idir = this_iface/2
  
        do mq = 1,meqn
           do j = 1,my
              deltam = fmneighbor0(j,mq) + efneighbor0(j,mq,1)
              deltap = fpneighbor1(j,mq) - efneighbor1(j,mq,1)
  
              qneighbor_dummy(0,j,mq)    = -deltam
              qneighbor_dummy(mx+1,j,mq) = -deltap
           enddo
  
           do i = 1,mx
              deltam = gmneighbor2(i,mq) + efneighbor2(i,mq,1)
              deltap = gpneighbor3(i,mq) - efneighbor3(i,mq,1)
  
              qneighbor_dummy(i,0,mq)    = -deltam
              qneighbor_dummy(i,my+1,mq) = -deltap
           enddo
        enddo
  
  
negative.code: c                 # Exchange at high side of 'this' grid in
  c                 # y-direction (idir == 1)
                    i1 = i
  c                  if (this_iface .eq. 2) then
  c                     j1 = 1
  c                  elseif (this_iface .eq. 3) then
  c                     j1 = my
  c                  endif
  c                  call fclaw2d_transform_face(i1,j1,i2,j2,
  c     &                  transform_cptr)
  c                  neighborval = qneighbor_dummy(i2,j2,mq)
  c                  neighborval = qthis_dummy(i1,j1,mq)
                    if (this_iface .eq. 2) then
                        j1 = 1
                        call fclaw2d_transform_face(i1,j1,i2,j2,
       &                      transform_cptr)
  c                      write(6,*) this_iface, i1, j1, i2, j2
                        gp = qthis_dummy(i2,j2,mq)
                        ef = qthis_dummy(i2,j2+1,mq)
                        neighborval = -(gp-ef)
                        delta = neighborval + gpthis2(i1,mq) 
       &                           - efthis2(i1,mq,0)
                        area = area2(i1)
                    else
  c                     # Coarse grid is bottom grid; fine is top grid   
  c                     # efc3(0) is flux stored in the coarse grid 
  c                     # interior cell.    
                        j1 = my
                        call fclaw2d_transform_face(i1,j1,i2,j2,
       &                      transform_cptr)
  c                      write(6,*) this_iface, i1, j1, i2, j2
                        gm = qthis_dummy(i2,j2,mq)
                        ef = qthis_dummy(i2,j2-1,mq)
                        neighborval = -(gm + ef)
  
                       delta = neighborval + gmthis3(i1,mq) + 
       &                            efthis3(i1,mq,0)
                       area = area3(i1)
  