说明：  matlab阶次分析，matlab实现的阶次分析算法，用于变转速机械故障特征提取，可运行，包含寻找脉冲时刻，等角度时刻，数字跟踪滤波，样条差值等步骤
(Matlab order analysis, the order analysis algorithm realized by MATLAB, is used to extract the fault features of variable speed machinery. It can be operated, including finding the pulse time, equal angle time, digital tracking filter, spline difference and other steps)