anchor.diff:  
     do i=0,4
       do j=0,4
  -      do k=0,4
  +!       do k=0,4
   
   ! Set experimental data
           t   = 1_dp
  
positive.code:            -Uc,  0,   0,  V, &
               0, Uf,   V,  0 /)
  
          call write_data(0.0_dp,0.3_dp)
        end do
      end do
    end do
  
  
negative.code:         x0  = 0.02_dp
          epsf= 0.1_dp*x0
          Uc  = 0.25_dp*i
          Uf  = 0.25_dp*i
          V   = 0.1_dp
  
  ! Set up matrix as an array of size 16
          Gkinv = (/ complex(dp) :: &
  