text: import numpy as np
  import matplotlib.pyplot as plt
  from fastrk import BT8713M, RKCodeGen
  
  # CRTBP ODE, https://github.com/BoberSA/fastrk/tree/master/examples/model_crtbp.py
  from model_crtbp import crtbp
  
  rk_module = RKCodeGen(BT8713M, autonomous=True).save_and_import()
  rk_prop = rk_module.rk_prop
  
  t0, t1 = 0., 3 * np.pi
  # initial state for halo orbit
  s0 = np.zeros(6)
  s0[[0, 2, 4]] = 9.949942666080747733e-01, 4.732924802139452415e-03, -1.973768492871211949e-02
  mc = np.array([3.001348389698916e-06])  # CRTBP constant
  rtol, atol = 1e-12, 1e-12
  
  # integrate CRTBP ODE from t0, s0 to t1
  arr = rk_prop(crtbp, s0, t0, t1, np.inf, rtol, atol, mc)
  
  plt.plot(arr[:, 1], arr[:, 2], 'r')
  plt.axis('equal')
  plt.show()