anchor.diff:      real(kind = x_precision), dimension(n_cell), intent(out) :: temperature_c  ! Temperature for the critical point
       real(kind = x_precision), dimension(n_cell), intent(out) :: sigma_c        ! Surface density for the critical point
       !------------------------------------------------------------------------
  -    integer                                     :: i,j,k
  +    integer                                     :: i,j,k          ! Iteration counters
   
       ! For variables
       real(kind = x_precision)                    :: f              ! Q+ - Q-
  
positive.code:       enddo
  
        ! For the first critical point (the one at the right of the S shape)
        call first_critical_point(sigma_t_thick, temperature, index_fcp, sigma_c_thick, temp_c_thick)
  
        ! For the second critical point (the one at the left of the S shape)
        call second_critical_point(sigma_t_thick, sigma_t_thin, temperature,&
         index_fcp, index_scp, sigma_c_thin, temp_c_thin)
  
        ! Combining the two separate curves into one that forms the S shape
        call build_s_curve(sigma_t_thick, sigma_t_thin, index_scp, sigma_real)
  
        temp_real = temperature
  
        call display_critical_points(sigma_c_thin, temp_c_thin, sigma_c_thick, temp_c_thick, k)
  
        ! Saving the DIMENSIONED values of Sigma and T for the S curve in a file
  
negative.code:       write(fid_tot,'(3(A16))') 'Surface_density', 'Temperature', 'Optical_depth'
  
        do j = 1, nb_it
          call variables(k, temperature(j), sigma(j), f, optical_depth, tau_eff)
  
          temp_real(j)  = temperature(j) * state_0%T_0
          sigma_real(j) = sigma(j) * state_0%S_0
  
          write(fid_tot,fmt = '(3(e16.6e2))') sigma_real(j), temp_real(j), tau_eff
        enddo
  