小波变换滤波方法，当调用wavefast函数发现matlab没有该函数，通过查阅找到了小波变换的m文件，保存成函数文件后就可以直接调用。(wave filter: The wavelet transform filtering method, when the call wavefast function finds that MATLAB does not have the function, it can be called directly after finding the m file of the wavelet transform and storing it as a function file)