[FieldTrip] ft_freqanalysis without ft_preprocessing

[Stenner, Max-Philipp]

Hi Alexis,
it may just be that ft_checkdata is unhappy with the subfields '.trials' and '.times' instead of '.trial' and '.time'.
Good luck,
best
Max

________________________________
Von: fieldtrip-bounces at science.ru.nl [fieldtrip-bounces at science.ru.nl]" im Auftrag von "Alexis [alexis.makin at liverpool.ac.uk]
Gesendet: Montag, 29. Juli 2013 18:03
Bis: FieldTrip discussion list
Betreff: Re: [FieldTrip] ft_freqanalysis without ft_preprocessing

Hi, thanks for your reply,

so that's what my data structure looks like.

Is it common to use fieldtrip functions on data which has already been cleaned and epoched elsewhere?

Alexis

On 29 Jul 2013, at 16:51, Eelke Spaak wrote:


Hi Alexis,

How does your data structure look exactly? I.e. what does matlab display when you type 'data' at the prompt? The error message suggests that it is not yet quite in the appropriate fieldtrip format.

Best,
Eelke

Op 29 jul. 2013 17:36 schreef "Alexis" <alexis.makin at liverpool.ac.uk<mailto:alexis.makin at liverpool.ac.uk>> het volgende:
Hi

I already have data which has been cleaned, filtered and artefact rejected etc.

It is now .mat format (trials X electrodes X time).

I can follow the advice from the wiki below to make a structure which should be compatible with ft_freqanalysis:

Alternatively, if you already are able to read the data into Matlab, you can reformat that data within Matlab into a datastructure that is compatible with FieldTrip. Raw data that is comparable with the output of preprocessing should consist of a structure with the fields

data.label   % cell-array containing strings, Nchan X 1
data.fsample % sampling frequency in Hz, single number
data.trial   % cell-array containing a data matrix for each trial (1 X Ntrial), each data matrix is    Nchan X Nsamples
data.time    % cell-array containing a time axis for each trial (1 X Ntrial), each time axis is a 1 X Nsamples vector
data.trialinfo % this field is optional, but can be used to store trial-specific information, such as condition numbers, reaction times, correct responses etc. The dimensionality is N x M

but when I try to run ft_freqanalysis(cfg, data) on this

I get the following error messages:

??? Error using ==> ft_checkdata at 366
This function requires raw, comp or mvar data as input.

Error in ==> ft_freqanalysis at 219
data = ft_checkdata(data, 'datatype', {'raw', 'comp',
'mvar'}, 'feedback', cfg.feedback, 'hassampleinfo', 'yes');

How to I tell the ft_checkdata function what datatype I have? Is this a simple problem?

Is it common to use fieldtrip functions on data which has already been preprocessed in another way? Or is this not advisable?

cheers,


Alexis
alexis.makin at liv.ac.uk<mailto:alexis.makin at liv.ac.uk>

Network: www.liv.ac.uk/perception-action/<http://www.liv.ac.uk/perception-action/>




_______________________________________________
fieldtrip mailing list
fieldtrip at donders.ru.nl<mailto:fieldtrip at donders.ru.nl>
http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
_______________________________________________
fieldtrip mailing list
fieldtrip at donders.ru.nl<mailto:fieldtrip at donders.ru.nl>
http://mailman.science.ru.nl/mailman/listinfo/fieldtrip

Alexis
alexis.makin at liv.ac.uk<mailto:alexis.makin at liv.ac.uk>

Network: www.liv.ac.uk/perception-action/<http://www.liv.ac.uk/perception-action/>