preprocessing without trigger...

[Ingrid Nieuwenhuis]

Hi,

There is actually a trial-function implemented in fieldtrip that you can use
during definetrial, it is called trialfun_general.

cfg.trialfun              = 'trialfun_general';
cfg.trialdef.triallength  = 2;
cfg.trialdef.ntrials      = inf;

And it will cut the data in 2 sec nonoverlapping timewindows. Nice and easy
:)

Best Ingrid

> -----Original Message-----
> From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On
> Behalf Of Nathan Weisz
> Sent: Monday, June 29, 2009 9:34 AM
> To: FIELDTRIP at NIC.SURFNET.NL
> Subject: Re: [FIELDTRIP] preprocessing without trigger...
>
> hi,
>
> if i understand you correctly you want to analyse your sponatneous data.
> you need a "trial-function" that you run before calling preprocessing
> (see help definetrial).
>
> below some code for *non-overlapping* 2s windows. but it should be
> easy to adapt.
>
> good luck,
> n
>
> function trl=tzvetan_trialf(cfg)
> %cuts data into 2 second windows
>
> hdr = read_fcdc_header(cfg.dataset);
> win=2*hdr.Fs;
>
> trl=[];
>
> i=1;
> k=1;
> while i < (hdr.nSamples-win-1)
>
>      trl(k,:)=round([i (i+win-1) 0]);
>      i=i+win;
>      k=k+1;
>
> end%i
>
> On 23.06.2009, at 14:20, Marco Rotonda wrote:
>
> > thanks!
> > it's very useful because I'm using bci2000 either!
> >
> >
> > On 23/giu/09, at 14:03, Thomas Dijkman wrote:
> >
> >> Hi,
> >>
> >> Check out this page in the documentation:
> >>
> >>
> http://fieldtrip.fcdonders.nl/faq/reading_is_slow_can_i_write_my_raw_data_
> to_a_more_efficient_file_format
> >>
> >> This will probably help you further.
> >>
> >> Regards,
> >>
> >> Thomas
> >>
> >>
> >> -----Oorspronkelijk bericht-----
> >> Van: FieldTrip discussion list namens Marco Rotonda
> >> Verzonden: di 23-6-2009 13:59
> >> Aan: FIELDTRIP at NIC.SURFNET.NL
> >> Onderwerp: [FIELDTRIP] preprocessing without trigger...
> >>
> >> Hi there,
> >> it could be a stupid question but I don't know how to solve it.
> >> I wish to analyze some data files I have (continuous signal,
> >> without any
> >> trigger).
> >> These data sets are 3 minutes of neurofeedback training and there
> >> are no
> >> trigger.
> >> I just want take all the 3 minutes and take each second overlapping
> >> 500ms.
> >> The point is that there are no trigger so I don't know how to do the
> >> preprocessing (where I have to specify the trigger, isn't it?).
> >>
> >> Thanks in advance
> >>
> >> ----------------------------------
> >> 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.
> >>
> >> ----------------------------------
> >> 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.
> >
> > ----------------------------------
> > 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.
>
> ----------------------------------
> 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.

----------------------------------
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.