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<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial>Hi
Brian,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial>indeed:
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial>in
fft(tmpX,g.padratio*g.winsize)</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial>the FFT
window used is equal to g.winsize*g.padratio.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial>You can
confirm that by looking at the frequency resolution deltaF.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial>Best,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial>Johannes</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=195264611-27092006><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
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<FONT face=Tahoma size=2><B>Von:</B> eeglablist-bounces@sccn.ucsd.edu
[mailto:eeglablist-bounces@sccn.ucsd.edu] <B>Im Auftrag von </B>Brian
Roach<BR><B>Gesendet:</B> Montag, 18. September 2006 17:21<BR><B>An:</B>
eeglab_maillist<BR><B>Betreff:</B> [Eeglablist] timef winsize and padratio
variables<BR></FONT><BR></DIV>
<DIV></DIV>Dear EEGlab users,<BR><BR>I have a question about a few optional
input arguments to the timef function in eeglab. In the timef.m file,
where the matlab fft function is called, the usage is fft(x,n) where x is an
array equal to all the frequencies at a particular time point (we are looping
through 1:timesout) and n is equal to the padratio * the fft window size
(winsize). The actual line of code is:<BR><FONT
face="Courier New, Courier">tmpX = fft(tmpX,g.padratio*g.winsize);<BR><BR>I am
wondering, does the padratio actually increase the size of the fft window?
The comments from<BR><BR>>>help fft<BR><BR>imply that the second argument
in fft(x,<B>n</B>) 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?<BR><BR>thanks,<BR>Brian</FONT> <BR></BODY></HTML>