anchor.diff:      i1 = A(i)
       do j=1, size(A)
           j1 = A(j)
  -        call set_next_eigeval(iunt, g, kpr, j1, i1, 0, w, dk, prg)
  +        call set_next_eigeval(iunt, g, kpc, j1, i1, 0, w, dk, prg)
       end do
   end do
   
  
positive.code: ! y
  do i = 1, size(A)
      i1 = A(i)
      call set_next_eigeval(iunt, g, kpr, 0, i1, 0, w, dk, prg)
  end do
  
  ! z
  do i = 1, size(A)
      i1 = A(i)
      call set_next_eigeval(iunt, g, kpr, 0, 0, i1, w, dk, prg)
  end do
  
  ! xy
  
negative.code:     i1 = A(i)
      do j=1, size(A)
          j1 = A(j)
          call set_next_eigeval(iunt, g, kpc, 0, j1, i1, w, dk, prg)
      end do
  end do
  
  