Problem with Fieldtrip conversion

[Vladimir Litvak]

Just to make things clearer for FT users, the D variable that you get
from spm_eeg_ft2spm cannot exist without dataset on the disk. It's
different from FT where data can be just a variable in the workspace.
The reason is indeed memory mapping. So you must have the two files
present two have a valid dataset.

I suggest again to post SPM-related questions to the SPM list (even
though I like getting good publicity for SPM on the FT list ;-)

Best,

Vladimir

On Fri, Mar 5, 2010 at 6:59 PM, Vladimir Litvak <v.litvak at ion.ucl.ac.uk> wrote:
> The second argument is not the name of the file from which you loaded
> the variable but the name for the SPM dataset that will be generated.
> E.g. if you specify 'test' you'll get two files test.mat and test.dat.
>
> Vladimir
>
> On Fri, Mar 5, 2010 at 5:51 PM, Michael Wibral <michael.wibral at web.de> wrote:
>> Dear Vladimir,
>>
>> Thanks for the quick reply. Yes, i started looking into it and I really like the first impression (not the speed though :-)).
>>
>> I solved the problem in the meantime. The reason was related to an unsuccesful update attempt. Sorry for the confusion! Could you let me know (and other FT users) the logic behind specifying the data twice, i.e. once as the loaded variable in the workspace and once as a filename. Is this related to memory mapped file use?
>>
>> Michael
>>
>> -----Ursprüngliche Nachricht-----
>> Von: Vladimir Litvak <v.litvak at ION.UCL.AC.UK>
>> Gesendet: Mar 5, 2010 4:17:49 PM
>> An: FIELDTRIP at NIC.SURFNET.NL
>> Betreff: Re: [FIELDTRIP] Problem with Fieldtrip conversion
>>
>>>Hi Michael,
>>>
>>>I'm glad to hear that you started looking at SPM :-)  This is more of
>>>an SPM than a Fieldtrip question so perhaps the discussion should move
>>>to the SPM mailing list. Just from looking at the error message the
>>>problem doesn't look familiar. Could you send me your file with the
>>>struct (via yousendit.com if it's big) and I'll try to reproduce it?
>>>
>>>Best,
>>>
>>>Vladimir
>>>
>>>On Fri, Mar 5, 2010 at 2:59 PM, Michael Wibral <michael.wibral at web.de> wrot=
>>>e:
>>>> Dear FT/SPM Listusers,
>>>>
>>>> I am having a (hopefully) trivial problem with converting Fieldtrip MEG d=
>>>ata structures to spm8.
>>>> Here's what I did:
>>>>
>>>> 0. Patch spm8 to r3684
>>>> 1. Load the Fieldtrip data from /path/filename. They contain a variable (=
>>>FTstruct) named DataFT.
>>>> 2. Call spm_eeg_ft2spm(DataFT, '/path/filename')
>>>>
>>>> The error I get is:
>>>>
>>>> checkmeeg: no channel type, assigning default
>>>> checkmeeg: no units, assigning default
>>>> checkmeeg: transform type missing, assigning default
>>>> checkmeeg: data scale missing, assigning default
>>>>
>>>> ??? Undefined function or method 'fname' for input arguments of type 'str=
>>>uct'.
>>>> Error in =3D=3D> file_array.subsref>access_fields at 129 =A0 =A0 =A0 =A0 =
>>>case 'fname', =A0 =A0 =A0t =3D fname(obj);
>>>>
>>>> Error in =3D=3D> file_array.subsref at 17 =A0 =A0 =A0 =A0 varargout =3D a=
>>>ccess_fields(obj,subs);
>>>>
>>>> Error in =3D=3D> checkmeeg at 203 =A0 =A0 if ~isa(meegstruct.data.y, 'fil=
>>>e_array') || isempty(fileparts(meegstruct.data.y.fname)) ...
>>>>
>>>> Error in =3D=3D> meeg.meeg at 109 =A0 =A0 =A0 =A0 [OK D] =3D checkmeeg(va=
>>>rargin{1}, 'basic');
>>>>
>>>> Error in =3D=3D> spm_eeg_ft2spm at 138 D =3D meeg(D);
>>>>
>>>> Any help is very much appreciated.
>>>>
>>>> Michael
>>>>
>>>> ----------------------------------
>>>> The aim of this list is to facilitate the discussion between users of the=
>>> FieldTrip =A0toolbox, to share experiences and to discuss new ideas for ME=
>>>G 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.