text: def comp_fill_factor(self):
      """Compute the fill factor of the winding
      """
      if self.winding is None:
          return 0
      else:
          (Nrad, Ntan) = self.winding.get_dim_wind()
          S_slot_wind = self.slot.comp_surface_wind()
          S_wind_act = (
              self.winding.conductor.comp_surface_active()
              * self.winding.Ntcoil
              * Nrad
              * Ntan
          )
  
          return S_wind_act / S_slot_wind
  