text: # -*- coding: utf-8 -*-
  
  from numpy import pi
  
  
  def comp_length(self):
      """Compute the length of the arc
  
      Parameters
      ----------
      self : Arc3
          An Arc3 object
  
      Returns
      -------
      length: float
          length of the arc
      """
  
      self.check()
  
      R = self.comp_radius()
  
      # Half circle
      return float(pi * R)
  