1.代码
clear
clc
% Load a signal.
load noisdopp
% Decompose the signal at level 3 with db1 wavelet packets using Shannon entropy.
wpt=wpdec(noisdopp,3,'db1','shannon');
% Plot the wavelet packet tree.
plot(wpt)
%Decompose packet(3,0)
wpt=wpsplt(wpt,[3 0]);
% or equivalently wpsplt(wpt,7).
% Plot wavelet packet tree wpt.
plot(wpt)
%Obtain the coefficients at the node (3,0). Plot the signal and coefficients.
cfs=wpcoef(wpt,[3 0]);
subplot(2,1,1)
plot(noisdopp)
title('Signal')
axis tight
subplot(2,1,2)
plot(cfs)
title('Packet (3,0) Coefficients')
axis tight2.运行结果
