[FieldTrip] problems with channel layout autoscaling by ft_prepare_layout

[David Groppe]

Hi Fieldtripians,
   I'm trying to export some EEGLAB data to Fieldtrip and am having
trouble plotting the data topographically. I constructed a layout file
for my 31 electrodes (see attached) and tried to plot the topography
of my data using ft_topoplotER.m.  This produced the attached figures
all_chans.jpg and just_scalp_chans.jpg.  The topography should look
like that in the attached image, eeglab_topo.jpg.  As you can see, the
electrodes are shrunk too far into the head and can be off center.
Trying to change the channel layout file to fix this has little effect
because ft_prepare_layout.m automatically normalizes the electrode
coordinates to fill a unit circle.  Given the topoplots in the
fieldtrip tutorial, there's obviously a way around this problem but
save for editing the ft_prepare_layout.m, I don't know what to do.
     thanks in advance for your help,
            -David

-- 
David Groppe, Ph.D.
dgroppe at cogsci.ucsd.edu
http://www.cogsci.ucsd.edu/~dgroppe/
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