code: def add_particles_ascii(self, s):
          
          for l in s.split("\n"):
              r = l.split()
              if len(r):
                  try:
                      r = [float(x) for x in r]
                      p = Particle(simulation=self, m=r[0], r=r[1], x=r[2], y=r[3], z=r[4], vx=r[5], vy=r[6], vz=r[7])
                      self.add(p)
                  except:
                      raise AttributeError("Each line requires 8 floats corresponding to mass, radius, position (x,y,z) and velocity (x,y,z).")
docs: Adds particles from an ASCII string. 
  
          Parameters
          ----------
          s : string
              One particle per line. Each line should include particle's mass, radius, position and velocity.