<div>This might be of use to you.</div><div>Check the output variables when running spectopo,</div><div>you should be able to tell which output variable (in your Matlab workspace)</div><div>holds the spectral values. You should then </div>
<div>be able to take the average of a set of columns or rows </div><div>that contain your data of interest. </div><div>For basic questions about matlab,</div><div>ask Google questions such as "Take average of a row of numbers MATLAB" , etc....</div>
<div>which will take you directly to Mathworks and other tutorials.</div><div>Basically any question you have, you can find some initial answer,</div><div>especially for basic work such as averaging a set of numbers.</div>
<div><br></div><a href="http://sccn.ucsd.edu/eeglab/allfunctions/spectopo.html">http://sccn.ucsd.edu/eeglab/allfunctions/spectopo.html</a><div><br></div><div><table width="100%" style="font-family:Arial;font-size:medium">
<tbody><tr valign="TOP"><td valign="TOP"><font face="Helvetica"><font size="+2"><b>SPECTOPO</b></font></font></td><td valign="BOTTOM"><font face="Helvetica">Plot the mean log spectrum of a set of data epochs at all channels as a bundle of traces. At specified frequencies, plot the relative topographic distribution of power. If available, uses pwelch() from the Matlab signal processing toolbox, else the EEGLAB <a href="http://sccn.ucsd.edu/eeglab/allfunctions/spectopo.html">spec</a> function. Plots the mean spectrum for all of the supplied data, not just the pre-stimulus baseline.</font></td>
</tr><tr valign="TOP"><td align="CENTER" colspan="2"><br></td></tr><tr valign="TOP"><td valign="TOP"><font face="Helvetica"><font size="+1"><b>Usage:</b></font></font></td><td valign="BOTTOM"><font face="Helvetica">>> spectopo(data, frames, srate);<br>
>> [spectra,freqs,speccomp,contrib,specstd] = spectopo(data, frames, srate, 'key1','val1', 'key2','val2' ...);</font></td></tr></tbody></table>
<br><br><div class="gmail_quote">On Thu, May 10, 2012 at 8:37 AM, Chen, Meixuan <span dir="ltr"><<a href="mailto:mc155@hw.ac.uk" target="_blank">mc155@hw.ac.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
<div dir="ltr">
<div dir="ltr"><font face="Arial" color="#000000">Hi, I have a question on how to calculate the power spectrum density of each frequency band, such as Alpha band frequency from 8-13Hz? I use EEGLab to plot the whole power spectrum on each channel with no problem, but when I want to look at the activity of each frenqucy band at different channels and under different conditions by comparing their power density, I don't know how to calculate the frequency band power on EEGLab, which is the whole frequency range power instead the power of certain frequency like 10Hz. From reviewing other people's works, I guess that I may need to integrate in the frequency band's power on Matlab. I am not very good at Matlab, still haven't solved out how to do it. Could anyone please give me some advice? </font></div>
<div dir="ltr"><font face="Arial"></font> </div>
<div dir="ltr"><font face="Arial">Many thanks.</font></div>
<div dir="ltr"><font face="Arial"></font> </div>
<div dir="ltr"><font face="Arial">Regards</font></div>
<div dir="ltr"><font face="Arial"></font> </div></div>
<div dir="ltr">
<address class="MsoNormal"><span style="FONT-SIZE:10pt;COLOR:navy;FONT-FAMILY:Arial"><font face="Courier New">Michelle Chen</font></span></address>
<address class="MsoNormal"><span style="FONT-SIZE:10pt;COLOR:navy;FONT-FAMILY:Arial">
<div align="left"><font><span style="FONT-SIZE:10pt;COLOR:navy;FONT-FAMILY:Arial"><font face="Courier New">Heriot-Watt University</font></span></font></div>
<div align="left"><font face="Courier New">Tel <a href="tel:%2B44%280%291896%20892268" value="+441896892268" target="_blank">+44(0)1896 892268</a><br></font><a href="mailto:mc155@hw.ac.uk" target="_blank"><font face="Courier New">mc155@hw.ac.uk</font></a><br>
</div></span></address></div><br>
<hr>
<br>
<font face="arial, helvetica" size="-1">
<b>Heriot-Watt University is the Sunday Times Scottish University of the Year 2011-2012.</b>
</font>
<br><br>
<font face="arial,helvetica" size="-2">
Heriot-Watt University is a Scottish charity registered under charity number SC000278.
<br>
</font>
</div>
<br>_______________________________________________<br>
Eeglablist page: <a href="http://sccn.ucsd.edu/eeglab/eeglabmail.html" target="_blank">http://sccn.ucsd.edu/eeglab/eeglabmail.html</a><br>
To unsubscribe, send an empty email to <a href="mailto:eeglablist-unsubscribe@sccn.ucsd.edu">eeglablist-unsubscribe@sccn.ucsd.edu</a><br>
For digest mode, send an email with the subject "set digest mime" to <a href="mailto:eeglablist-request@sccn.ucsd.edu">eeglablist-request@sccn.ucsd.edu</a><br></blockquote></div><br></div>