For wavelet decomposition of EEG signals

wavelet-decomp.m

%Applying bandpass filter to filter out the unwanted signal <4 and >30Hz
yy1=bandpass(SSS1,[4 30],128);
%Apply DWT at 5 level of decomposition
waveletFunction = 'db2';
[C,L] = wavedec(yy1,5,waveletFunction);
cD11 = detcoef(C,L,1);                   
cD21 = detcoef(C,L,2);                  
cD31 = detcoef(C,L,3);                   
cD41 = detcoef(C,L,4);                  
cD51 = detcoef(C,L,5);                  
cA51 = appcoef(C,L,waveletFunction,5);   
D11 = wrcoef('d',C,L,waveletFunction,1); %Gamma
D21 = wrcoef('d',C,L,waveletFunction,2); %Beta
D31 = wrcoef('d',C,L,waveletFunction,3); %Alpha
D41 = wrcoef('d',C,L,waveletFunction,4); 
D51 = wrcoef('d',C,L,waveletFunction,5); 
A51 = wrcoef('a',C,L,waveletFunction,5); 
%Find the mean
av1 = mean(D31);
%Find the standard deviation
sdA1 = std(D31);