[Eeglablist] calculation of spectral Power

[Don Scott]

Hello,

I have a question about how channel spectra are calculated.  The Plot menu
calls pop_prop() which, in turn, appears to call (line 215) Spoectopo.m for
the actual calculations using Welch's method (line 277) .  Then in line
306+ the calculations occur, maybe rescaled by some kind of RMS value?
the plot eventually displayed shows the ordinate label as "Power
10*log10(uv^2/Hz)"

I have tried to duplicate the EEGLAB results using the Matlab Signal
Processing toolbox but cannot get the same numbers given by EEGLAB.
Rescaling the sptool results by 10*log10(uv^2)/Hz) does not seem to help
either.

Can someone please help me clear this up, or point out what I am missing?
I need to know which is the correct set of data.

Thank you
Don


-- 
Don Scott

(864) 415 - 1795
Dscott8201 at Gmail.Com

*"Although the universe doesn't have an end, it had a beginning in the Big
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nowhere before the Big Bang, just as there is nowhere south of the South
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*
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*--- Stephen Hawking*
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