[FieldTrip] Channel_selection

[Max Cantor]

Here is how I do it:

allchan = ft_read_header(dataset);

(preprocess)

allchan.label = [allchan.label; implicitref];

(after artifact rejection/ICA/etc.)

badchan  = ft_channelselection('gui', allchan.label);

This gives me the channel labels for all channels, with the implicitref
added back in (normally this is removed), then a gui which lets me remove
bad channels manually after preprocessing/artifact rejection/ICA/etc.

Hope this helps.

Max Cantor
Research Assistant
Computational Neurolinguistics Lab
University of Michigan


On Wed, Nov 27, 2013 at 10:46 AM, "Jörn M. Horschig" <
jm.horschig at donders.ru.nl> wrote:

> Hi Frederico,
>
> I think the best solution is to not use fieldtrip but plain matlab
> function. This is a small example that might help you:
>
> >> allchans = {'Fz', 'Cz', 'CPz'};
> >> badchans = {'Fz', 'Cz'};
> >> idx = ismember(allchans, badchans)
>
> idx =
>
>      1     1     0
>
> You can then use the idx variable and logical indexing to get the good
> channels:
>
> >> allchans(~idx)
>
> ans =
>
>     'CPz'
>
> And then use cfg.channel = allchans(~idx).
>
> Be aware that ismember is a tricky function, because it returns the
> indices of the first vector as the first return variable and the respective
> same for the second vector as the second return variable, so order does
> matter. Just give it a try and play a bit around with it and you'll see.
>
> Best,
> Jörn
>
>
>
> Federico Grande wrote:
>
>> Hello everyone,
>>
>> In order to clean a little bit more my measurements, I have developed a
>> method which detects bad channels, and now, once I have the labels of the
>> bad channels, I want to give it to ft_preprocessing, but I don't know how.
>> I've been looking on ft_channelselection, and it seems that there is an
>> option , by using some like channel={'all','-channel to exclude'}. I have
>> an array with the labels of this channels that I want to exclude, but I
>> don't know why, it seems that I am not using it in the proper way. I have
>> tried  with cfg.channel= {'all','-badSelections'} (badSelections is my
>> array), and it doesn't work, since after processing, still appear all the
>> channels in the dat.label.
>>
>> Any suggestion?
>>
>> Thank you very much!!
>>
>> All the best,
>>
>> Federico Grande
>> _______________________________________________
>> fieldtrip mailing list
>> fieldtrip at donders.ru.nl
>> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
>>
>
>
> --
> Jörn M. Horschig
> PhD Student
> Donders Institute for Brain, Cognition and Behaviour
> Centre for Cognitive Neuroimaging
> Radboud University Nijmegen
> Neuronal Oscillations Group
> FieldTrip Development Team
>
> P.O. Box 9101
> NL-6500 HB Nijmegen
> The Netherlands
>
> Contact:
> E-Mail: jm.horschig at donders.ru.nl
> Tel:    +31-(0)24-36-68493
> Web: http://www.ru.nl/donders
>
> Visiting address:
> Trigon, room 2.30
> Kapittelweg 29
> NL-6525 EN Nijmegen
> The Netherlands
>
>
> _______________________________________________
> 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/20131127/0809eaaf/attachment-0002.html>