针对肖田元教授所著的《系统仿真导论》中龙格库塔法参考程序研究生很难看懂的现象，我加上了注释,使初学者能把学习算法和编写程序对应起来，从而可以有效地掌握算法的实现，对于用龙格库塔法进行在线实时仿真、建模、最优控制及自适应控制的教学有意义。-Professor Xiao Tianyuan for the book " Introduction to System Simulation,"　in reference to Runge-Kutta method is difficult to understand the phenomenon of post-graduate program, I have added comments to beginners can learn the corresponding algorithms and programming together, which could effectively implementation of control algorithms, using Runge-Kutta method for online real-time simulation, modeling, optimal control and adaptive control of a meaningful education.