old_contents: """Various tools for electomagntism physics
  
  Variables comonly used in the package
  -------------------------------------
  
  bw = Bandwidth
  cl : Correlation length
  epsilon, ep : Electric permittivity
  mp : Magnetic permeability
  nRCS : Normalized Radar Cross Section
  RCS : Radar Cross Section
  n : Optical index
  R : Reflection coefficient
  sigma_h, sh : Root Mean Square height
  theta, th : angle
  T : Transmission coefficient
  wf : Wave frequency
  wk : Wave number
  wl : Wavelength
  """
  
  __author__ = 'Cyril Grima'
  
  __all__ = ['iem', 'roughness', 'utils']
  
  from Classdef import *
  
  import iem
  import roughness
  import utils
  
new_contents: """Various tools for electomagntism physics
  
  Variables comonly used in the package
  -------------------------------------
  
  bw = Bandwidth
  cl : Correlation length
  epsilon, ep : Electric permittivity
  mp : Magnetic permeability
  nRCS : Normalized Radar Cross Section
  RCS : Radar Cross Section
  n : Optical index
  R : Reflection coefficient
  sigma_h, sh : Root Mean Square height
  theta, th : angle
  T : Transmission coefficient
  wf : Wave frequency
  wk : Wave number
  wl : Wavelength
  """
  
  __author__ = 'Cyril Grima'
  
  __all__ = ['iem', 'invert', 'roughness', 'utils']
  
  from Classdef import *
  
  import iem
  import invert
  import roughness
  import utils
  
subject: add invert module