[Eeglablist] timef winsize and padratio variables

[arno]

Dear Brian,
> tmpX = fft(tmpX,g.padratio*g.winsize);
>
> I am wondering, does the padratio actually increase the size of the 
> fft window?  The comments from
>
> >>help fft
>
> imply that the second argument in fft(x,*n*) is the window size.  This 
> would mean that the FFT window used by timef is not actually equal to 
> the winsize, but the winsize*padratio.  That can be a big difference, 
> depending on how large the padratio.  Is that actually true?  If so, 
> why does the command line spit out "results are oversampled N times" 
> where N = padratio?  Are the results actually oversampled or is the 
> FFT window size just that much larger?  I understand that the larger 
> the padratio, the more frequency output bins returned (and the smaller 
> these are), but if the padratio does not just make the fft window 
> larger, what is it doing and why would it not always be set to 1?
tmpX is the data itself and has a size equal to g.winsize. This is what 
we call the window size. The g.padratio factor only multiply this window 
size (0 padding) to artificially increase the frequency resolution. I 
agree that the documentation is not totally clear and we will make it 
clearer.

Hope this helps,

Arno

> thanks,
> Brian
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