code: def get_median_area(self, mag, rake):
          
          # strike slip
          length = 10.0 ** (-2.57 + 0.62 * mag)
          seis_wid = 20.0
  
          # estimate area based on length
          if length < seis_wid:
              return length ** 2.
          else:
              return length * seis_wid
docs: The values are a function of magnitude.