anchor.diff: -module mod_S_curve
  +module mod_s_curve
     use mod_constants
     use mod_read_parameters
     use mod_variables
  
positive.code:          K_e, tau_eff, P_rad, P_gaz,E_ff,Fz,f_center,Sigma_0, Omega_0,rs,T_0, rho_0)
  
  
            if(f_min * f_center .gt. 0.) then
  
               Smin         = Scenter
  
            else if (f_max * f_center .gt. 0.) then
               Smax         = Scenter
  
            endif
  
            Scenter       = (Smin + Smax) * 1._x_precision / 2._x_precision
  
            j               = j + 1
  
  
negative.code:     write(*,*)'fmin = ',f_min
      write(*,*)'fmax = ',f_max
  
      if ( f_max * f_min > 0.) then
         write(*,*)'This function image does not switch its sign in this particular interval.'
      endif
  
      if( f_max * f_min > 0.) then
         iteration:do while ( dabs( Smax - Smin ) >= eps .and. j < 10000)
  
  
      call variables(T, Smin, Omega, H, rho, cs, nu, Q_plus, Q_minus, K_ff, K_e,&
  