[FieldTrip] define trials from multiple datasets

Arjen Stolk a.stolk8 at gmail.com
Thu Feb 11 01:18:40 CET 2016


I see now you wrote 8 sessions with the same subject. You could make a loop
that conceptually looks like this:

for s = 1:numsessions

cfg = ft_definetrial(cfg);
data{s} = ft_preprocessing(cfg);

end
data_all = ft_appenddata([], data{:});

2016-02-10 16:15 GMT-08:00 Arjen Stolk <a.stolk8 at gmail.com>:

> Hi Max,
>
> See these pages and judge for yourself:
>
> http://www.fieldtriptoolbox.org/example/getting_started_with_reading_raw_eeg_or_meg_data
>
> http://www.fieldtriptoolbox.org/example/making_your_own_trialfun_for_conditional_trial_definition
>
> If your trials are defined as x1 time before a certain trigger until x2
> time after, it's very easy. If it's slightly more complicated, then check
> that second page. In short, the idea there is to make ft_definetrial call a
> tailormade trial function (cfg.trialfun). The good news is that if the
> triggers and trials are the same for each subject, you only have to make
> one function.
>
> Hope that gets you started,
> Arjen
>
> 2016-02-10 16:03 GMT-08:00 Max Cantor <Max.Cantor at colorado.edu>:
>
>> Hi fieldtrip community,
>>
>> I'm trying to use ft_definetrial to create a trial definition from 8
>> datasets, recorded back-to-back from a subject, and then use
>> ft_redefinetrial with that trial definition and raw data that was
>> concatenated in eeglab and converted to a fieldtrip structure using
>> eeglab2fieldtrip. Is this feasible in a relatively straightforward way, or
>> would I be better off doing the epoching in eeglab as well before
>> converting back to fieldtrip?
>>
>> On a side note, I chose to concatenate the data in eeglab because I could
>> not figure out a convenient way to do so in fieldtrip. I know there is
>> ft_appenddata, but as best as I can tell this is meant to be used after
>> epoching, and the sample information was not being concatenated (or at
>> least not properly), which was creating problems down the line with
>> artifact rejection in my pipeline. Maybe there was some other way to do
>> this properly in fieldtrip that I had not considered in the first place.
>>
>> Best,
>>
>> Max
>>
>> --
>> Max Cantor
>> Graduate Student
>> Cognitive Neuroscience of Language Lab
>> University of Colorado Boulder
>>
>> _______________________________________________
>> fieldtrip mailing list
>> fieldtrip at donders.ru.nl
>> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20160210/5d47d305/attachment-0002.html>


More information about the fieldtrip mailing list