[Eeglablist] FFT in EEG signal

[arno delorme]

Dear Starz,

If X is the data, nfft the size of the FFT window and srate the  
sampling rate. The formula below will do all channels at once if they  
are in the first dimension.

     tmp   = fft(X, nfft, 2);
     f     = linspace(0, srate/2, size(tmp,2)/2);
     f     = f(2:end); % remove DC (match the output of PSD)
     tmp   = tmp(:,2:size(tmp,2)/2,:); % the FFT decomposition is  
symmetrical
     res   = 10*log10(mean(abs(tmp).^2,3));
     figure; plot(f, res);

best,

Arno

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