BDF file problems

Joseph Brooks joseph.brooks at UCL.AC.UK
Fri Nov 13 22:21:57 CET 2009

I'm new to Fieldtrip. I am working with Biosemi data (BDF file format).
I've come across a problem when defining trials. I've come up with a
work-around but I'm interested in whether others have encountered this
problem and I want to alert the fieldtrip developers of this potential
problem. I've tried it on several BDF files. Here is an example of my
input and the error...

cfgSSVEP                         = [];
cfgSSVEP.dataset                 = [pathname,filename];
cfgSSVEP.trialdef.eventtype      = 'STATUS';
cfgSSVEP.trialdef.eventvalue     = {'21' '22'};
cfgSSVEP.trialdef.prestim        = 1;
cfgSSVEP.trialdef.poststim       = 16;

cfgSSVEP.dataset      = [pathname,filename];
cfgSSVEP              = definetrial(cfgSSVEP);
cfgSSVEP.padding      = 0;
cfgSSVEP.continuous   = 'yes';
evaluating trialfunction 'trialfun_general'
Warning: Out of range value or NaN computed in integer arithmetic.
 > In read_event at 281
  In trialfun_general at 50
  In definetrial at 139
??? Error using ==> cellstr at 34
Input must be a string.

Error in ==> cell.intersect at 44
    a = cellstr(a);

Error in ==> trialfun_general at 104
  elseif ~isempty(intersect(event(i).value, cfg.trialdef.eventvalue))

Error in ==> definetrial at 139
    [trl, event] = feval(cfg.trialfun, cfg);


I've managed to "fix" the problem by changing line 104 in
trialfun_general to:

elseif ~isempty(intersect(num2str(event(i).value), cfg.trialdef.eventvalue))

Any feedback will be much appreciated...

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 and

More information about the fieldtrip mailing list