说明：  y=d2wavelet(x,Fs,level) does the 2nd order Daubechies Wavelet Transform of signal x with a sampling frequency Fs and the DWT is decomposition is done upto a level It returns the matrix of all decompositions and the final approximations. Instead of using the matlab s inbuilt DWT function, this file explains the algorithm for DWT. Mostly useful for learning & academic purposes. For other wavelets, the filter values alone can be changed or WFILTERS can be used. The function basically is for Condition Monitoring of rotating equipments by vibration based bearing fault diagnosis by the author. Example: clear all t=[0:0.0003:8*pi] x=sin(5000*t)+sin(1000*t) x=x(1:2^16) level=5 Fs=1/0.003 d2wavelet(x,Fs,level) Thanks for Downloading. Don t forget to rate or comment.