Help with dipolesimulation

[jan-mathijs schoffelen]

Dear Luis,

I guess that the desired functionality is already there, the only  
thing which you have to do is specifying your input configuration  
meaningfully.
The most relevant line is line 215, which states (more or less) trial  
= lf * dipmom * dipsignal;

lf contains the leadfield (forward model) for the dipoles at the  
positions in cfg.dip.pos, and has dimensionality Nchan x (Ndipolex3),  
so it is a concatenation (in the columns) of the single position's  
leadfields.
dipsignal is an NdipolexNtime matrix containing the dipoles' time  
series.
For the matrix product to work, dipmom should be of dimensionaity  
(Ndipolex3)xNdipole (right?). This is the key to the solution to your  
problem:

cfg.dip.mom should be something like  [orix1 0;oriy1 0; oriz1 0;0  
orix2;0 oriy2;0 oriz2], with ori(xyz)(1/2) specifying the moments of  
your dipoles.

I hope this helps,

Jan-Mathijs


On Apr 18, 2009, at 12:20 PM, Luis Morán wrote:

> Hi dear Fieldtrippers!!
>
> I'm trying to make a dipolesimulation with two dipoles. I need to  
> use different frequencies and phases for each dipole and I don't  
> know very well how to modify the dipolesimulation function.
>
> Any advice?
>
> Thanks in advance
>
> Best regards
> -- 
> Luis Morán Rodríguez
>
> Bioengineering Group
> Universidad Politecnica Madrid
> ----------------------------------
>
> The aim of this list is to facilitate the discussion between users  
> of the FieldTrip toolbox, to share experiences and to discuss new  
> ideas for MEG and EEG analysis.
>
> http://listserv.surfnet.nl/archives/fieldtrip.html
>
> http://www.ru.nl/fcdonders/fieldtrip/
>

----------------------------------
The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/neuroimaging/fieldtrip.