[Eeglablist] newtimef baselining

[Chris Bishop]

Hello,

I'm a relatively new user to EEGLAB and have what looks like an error in
thew 'newtimef' function, but it's so glaring that I can't help but believe
that I have a fundamental misunderstanding of what the function newtimef
function is supposed to do.

I'm using eeglab7.2.9.20b.

I'm trying to perform spectrotemporal decompositions on single trials.
 Strangely, the pre-stimulus period used for the baseline has a non-zero
mean after returning from newtimef.  For instance, if you place a break
point at line 2005, you'll notice that the value removed from Pout (Pout =
Pout - 10*repmat(log10(mbase),[1 length(timesout)]);) leads to a non-zero
baseline in Pout (Pout(:,baseln)~=0).  It's off by several dB for most
trials.  I think this might be because the averaging used to create mbase,
the power of the baseline period, is done BEFORE the log transformation into
decibels rather than after.  So, the baseline period of Pout and the mean of
mbase are not the same.

Has anyone else experienced this issue?  Am I just missing something?  I
apologize if I'm making some silly mistake ...

Thanks,
-Chris
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