>> ls=length(a);
[c,l]=wavedec(a,7,'db4');
ca7=appcoef(c,l,'db4',7);
cd7=detcoef(c,l,4);
cd6=detcoef(c,l,4);
cd5=detcoef(c,l,4);
cd4=detcoef(c,l,4);
cd3=detcoef(c,l,3);
cd2=detcoef(c,l,2);
cd1=detcoef(c,l,1);
d7=wrcoef('d',c,l,'db1',7);
d6=wrcoef('d',c,l,'db1',6);
d5=wrcoef('d',c,l,'db1',5);
d4=wrcoef('d',c,l,'db1',4);
d3=wrcoef('d',c,l,'db1',3);
d2=wrcoef('d',c,l,'db1',2);
d1=wrcoef('d',c,l,'db1',1);
figure(1);
subplot(311);plot(cd3);
Ylabel('cd3');
subplot(312);plot(cd2);
Ylabel('cd2');
subplot(313);plot(cd1);
Ylabel('cd1');
a=
figure(2);
subplot(811);plot(a7);
title('小波分析7层分解');Ylabel('a0');
for i=1:7
decmp=wrcoef('d',c,l,'db4',7-i);
subplot(8,1,i+1);
>> ls=length(a);
>> [c,l]=wavedec(a,7,'db6');
>> a6=wrcoef('a',c,l,'db6',7);
>> d7=wrcoef('d',c,l,'db6',7);
>> d6=wrcoef('d',c,l,'db6',6);
>> d5=wrcoef('d',c,l,'db6',5);
>> d4=wrcoef('d',c,l,'db6',4);
>> d3=wrcoef('d',c,l,'db6',3);
>> d2=wrcoef('d',c,l,'db6',2);
>> d1=wrcoef('d',c,l,'db6',1);
>> figure(4);
>> subplot(511);plot(a7);ylabel('a7');
>> subplot(512);plot(d4);ylabel('d4');
>> subplot(513);plot(d3);ylabel('d3');
>> subplot(514);plot(d2);ylabel('d2');
>> subplot(515);plot(d1);ylabel('d1');
>> ls=length(a);
>> [c,l]=wavedec(a,4,'db4');
>> a4=wrcoef('a',c,l,'db4',4);
>> d4=wrcoef('d',c,l,'db4',4);
>> d3=wrcoef('d',c,l,'db4',3);
>> d2=wrcoef('d',c,l,'db4',2);
>> d1=wrcoef('d',c,l,'db4',1);
>> figure(5);
>> subplot(111);plot(a4);
>> ls=length(a);
>> [c,l]=wavedec(a,7,'db6');
>> a7=wrcoef('a',c,l,'db6',7);
>> figure(8);
>> subplot(111);plot(a7);ylabel('a7');
>> ls=length(a);
>> [c,l]=wavedec(a,7,'db6');
>> a6=wrcoef('a',c,l,'db6',7);
>> d7=wrcoef('d',c,l,'db6',7);
>> d6=wrcoef('d',c,l,'db6',6);
>> d5=wrcoef('d',c,l,'db6',5);
>> d4=wrcoef('d',c,l,'db6',4);
>> d3=wrcoef('d',c,l,'db6',3);
>> d2=wrcoef('d',c,l,'db6',2);
>> d1=wrcoef('d',c,l,'db6',1);
>> figure(6);
>> subplot(211);plot(a7);ylabel('a7');
>> subplot(212);plot(d1);ylabel('d1');
>> ls=length(a);
>> [c,l]=wavedec(a,7,'db6');
>> a7=wrcoef('a',c,l,'db6',7);
>> d7=wrcoef('d',c,l,'db6',7);
>> d6=wrcoef('d',c,l,'db6',6);
>> d5=wrcoef('d',c,l,'db6',5);
>> d4=wrcoef('d',c,l,'db6',4);
>> d3=wrcoef('d',c,l,'db6',3);
>> d2=wrcoef('d',c,l,'db6',2);
>> d1=wrcoef('d',c,l,'db6',1);
>> figure(1);
>> subplot(311);plot(a7);ylabel('a7');
>> subplot(312);plot(d2);ylabel('d2');
>> subplot(313);plot(d1);ylabel('d1');