中文说明：非线性振动相关介绍，时域图、频率图、分叉图、轴心轨迹、poincare截面、相图、Lyapunov指数（李雅普诺夫指数）等相关基础知识和matlab编程。
English Description：
Nonlinear vibration related introduction, time domain diagram, frequency diagram, bifurcation diagram, axis trajectory, Poincare section, phase diagram, Lyapunov exponent (Lyapunov exponent) and other related basic knowledge and MATLAB programming.