check_collisions Subroutine

  subroutine check_collisions(report_unit)
    use warning_helpers, only: is_zero
    implicit none
    integer, intent(in) :: report_unit
    select case (collision_model_switch)
    case (collision_model_lorentz,collision_model_lorentz_test)
       write (report_unit, fmt="('A Lorentz collision operator has been selected.')")
       if (cfac > 0) write (report_unit, fmt="('This has both terms of the Lorentz collision operator: cfac=',e12.4)") cfac
       if (is_zero(cfac)) write (report_unit, fmt="('This is only a partial Lorentz collision operator (cfac=0.0)')")
       if (const_v) write (report_unit, fmt="('This is an energy independent Lorentz collision operator (const_v=true)')")  
!          if (hypercoll) call init_hyper_lorentz
    case (collision_model_full)
       write (report_unit, fmt="('Full GS2 collision operator has been selected.')")
    end select
  end subroutine check_collisions