code: def sca_intensity(scatterer, h_pol=True):
      
      Z = scatterer.get_Z()
      return (Z[0,0] - Z[0,1]) if h_pol else (Z[0,0] + Z[0,1])
docs: Scattering intensity (phase function) for the current setup.    
  
      Args:
          scatterer: a Scatterer instance.
          h_pol: If True (default), use horizontal polarization.
          If False, use vertical polarization.
  
      Returns:
          The differential scattering cross section.