%裝載采集的信號leleccum.mat
load leleccum;
%將信號中第2200到第3600個(gè)采樣點(diǎn)賦給s
index=2200:3600;
s=leleccum(index);
%畫出原始信號
figure(1);
plot(index,s);
xlabel('樣本序號 n');
ylabel('幅值 A');
%用db3小波進(jìn)行5層分解
[c,l]=wavedec(s,5,'db3');
%重構(gòu)第1-5層細(xì)節(jié)系數(shù)
d5 = wrcoef('d',c,l,'db3',5);
d4 = wrcoef('d',c,l,'db3',4);
d3 = wrcoef('d',c,l,'db3',3);
d2 = wrcoef('d',c,l,'db3',2);
d1 = wrcoef('d',c,l,'db3',1);
%顯示細(xì)節(jié)系數(shù)
figure(2)
subplot(3,1,1);
plot(index,d3,'LineWidth',2);
ylabel('d3');
subplot(3,1,2);
plot(index,d2,'LineWidth',2);
ylabel('d2');
subplot(3,1,3);
plot(index,d1,'LineWidth',2);
ylabel('d1');
xlabel('樣本序號 n');