anchor.diff:    ! Range of surface density [Smin, Smax] and temperature [T_min, T_max]
     ! values should be changed in order to find more coherent results
     !-------------------------------------------------------------------------
  -  subroutine curve()
  -    implicit none
  +  subroutine curve( temperature, s)
  +    implicit none
  +
  +    real(kind = x_precision),dimension(n_cell),intent(out)  :: temperature
  +    real(kind = x_precision),dimension(n_cell),intent(out)  :: s
  +
       integer                                                :: i     = 0
  -    !integer                                                :: j     = 0
       integer                                                :: k     = 0
       integer                                                :: l     = 0
   
  
positive.code:     ! eps -> Precision
      ! T-> Fixed variable
      !-------------------------------------------------------------------------
      dichotomy             = (Smin+Smax)/2.
      j = 0
      call variables(T, Smin, Omega, H, rho, cs, nu, Q_plus, Q_minus, K_ff, K_e,&
           tau_eff, P_rad, P_gaz,E_ff,Fz,f_min,Sigma_0, Omega_0,rs,T_0,rho_0,optical_depth)
  
negative.code: 
      if ( f_max * f_min .gt. 0.) then
     !    write(*,*)'This function image does not switch its sign in this particular interval.'
       !  dichotomy = 0
  
      else if( f_max * f_min .lt. 0.) then
         iteration:do while ( dabs( Smax - Smin ) .ge. eps .and. j .lt. 10000)
  