anchor.diff:               diag = cA(4,k,jm,i)+cA(4,km,jm,i)+cA(4,k,jm,im)+cA(4,km,jm,im) + diag
                diag = cA(7,k,j,im)+cA(7,km,j,im)+cA(7,k,jm,im)+cA(7,km,jm,im) + diag
   
  +             if (k2 == 1) then
  +             ! add the horizontal diagonal connections in the bottom level
  +             diag = cA(5,k,j,im)  + diag
  +             diag = cA(8,k,jm,im) + diag
  +             endif
   
                ! double that to account for symmetry of connections, we've now 40 terms
                diag = diag+diag
  
positive.code:              ! here is the first 20
  
               diag = 0._8
               diag = cA(2,km,j,i)+cA(2,km,jm,i)+cA(2,km,j,im)+cA(2,km,jm,im) + diag
               diag = cA(5,km,jm,i)+cA(5,km,jm,im)                            + diag!bug fixed in cA5
               diag = cA(8,km,j,im)+cA(8,km,jm,im)                            + diag
  
negative.code:                                    +cA(3,kp,jm,i)+cA(3,kp,jm,im) &
                                     +cA(6,kp,j,im)+cA(6,kp,jm,im) )
               ! cA(5,:,:,:)      -> p(k-1,j-1,i)
               cA2(5,k2,j2,i2) = cff*(cA(5,k,j,i)+cA(5,k,j,im)) 
               ! cA(8,:,:,:)      -> p(k-1,j,i-1)
               cA2(8,k2,j2,i2) = cff*(cA(8,k,j,i)+cA(8,k,jm,i)) 
               else ! bottom level = horizontal diagonal cross terms
                  ! cA(5,:,:,:)      -> p(k,j+1,i-1)
                  ! cA(8,:,:,:)      -> p(k,j-1,i-1)
               cA2(2,k2,j2,i2) = 0._8
               cA2(5,k2,j2,i2) = cff*cA(5,k,jm,i) 
               cA2(8,k2,j2,i2) = cff*cA(8,k,j,i) 
               endif
  
               if (k2 < nz2) then
               ! cA(3,:,:,:)      -> p(k+1,j-1,i)
               cA2(3,k2,j2,i2) = cff*(cA(3,km,j,i)+cA(3,km,j,im)) 
               ! cA(6,:,:,:)      -> p(k+1,j,i-1)
               cA2(6,k2,j2,i2) = cff*(cA(6,km,j,i)+cA(6,km,jm,i)) 
               else
               cA2(3,k2,j2,i2) = 0._8
               cA2(6,k2,j2,i2) = 0._8
               endif
               ! cA(4,:,:,:)      -> p(k,j-1,i)
               cA2(4,k2,j2,i2) = cff*(cA(4,k,j,i)+cA(4,km,j,i) &
                                     +cA(4,k,j,im)+cA(4,km,j,im) &
                                     +cA(5,km,j,i)+cA(5,km,j,im) & 
                                     +cA(3,k ,j,i)+cA(3,k ,j,im) ) 
  
               ! cA(7,:,:,:)      -> p(k,j,i-1)
               cA2(7,k2,j2,i2) = cff*(cA(7,k,j,i)+cA(7,km,j,i) &
                                     +cA(7,k,jm,i)+cA(7,km,jm,i) &
                                     +cA(8,km,j,i)+cA(8,km,jm,i) &
                                     +cA(6,k ,j,i)+cA(6,k ,jm,i) )
  
  
               ! the diagonal term is the sum of 48 terms ...             
  