[Eeglablist] ERP Polarity Flip

[Arnaud Delorme]

Dear Ahmed,

To invert the polarity of all components - which as mentioned several times on this list still represents a valid ICA decomposition - on the Matlab command line, type 

ALLEEG.icaweights = -ALLEEG.icaweights;
ALLEEG.icawinv = -ALLEEG.icawinv;
ALLEEG.icaact = -ALLEEG.icaact;

For a whole STUDY, loop on all datasets.
Then if you want to update the EEGLAB interface

[ALLEEG EEG CURRENTSET] = eeg_store(ALLEEG, EEG, CURRENTSET);
eeglab redraw;

Arno

On Oct 13, 2014, at 1:40 PM, Ahmed Almurshedi <ahmed19875000 at yahoo.com> wrote:

> Dear All,
> 
> Is there any way to flip the polarity (Peak become trough and vice versa) of ERP and components dataset  or whole study?
>  
> Thanks
> 
> AHMED
> _______________________________________________
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to eeglablist-unsubscribe at sccn.ucsd.edu
> For digest mode, send an email with the subject "set digest mime" to eeglablist-request at sccn.ucsd.edu

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sccn.ucsd.edu/pipermail/eeglablist/attachments/20141106/92539278/attachment.html>