neuromag data analysis

[Virginie van Wassenhove]

Dear Vladimir,

thanks for your quick reply. I had double-checked the signal processing
toolboxes appear in my path so not sure what is going on there but will
double-check this shortly...

Virginie

Virginie.van-Wassenhove at cea.fr
Virginie.van.Wassenhove at gmail.com


> Dear Virginie,
>
> It looks very much like the problem is in your Matlab. The first error
> is definitely a result of missing signal processing toolbox. The
> second one looks like a version thing, but I'm not sure. If I
> understand correctly the third one, it might have to do with the
> absence of image processing toolbox that is used to compute clusters.
>
> Best,
>
> Vladimir
>
>
>
> On Tue, Jan 13, 2009 at 5:01 PM, Virginie van Wassenhove
> <vvw at caltech.edu> wrote:
>> Hello Fieldtrip-ers and happy new year!
>>
>> I am trying to get some Neuromag (MEG) data analysis done with Fieldtrip
>> - so
>> far I had used fieldtrip for EEG. I can read the data fine (segmentation
>> via
>> meg-pd) but there are a couple of issues now.
>>
>> 1. when I try to filter or downsample I am receiving the following
>> errors:
>>
>> %FILTER (lpf specified in cfg)
>> blah = timelockanalysis(cfg,data_std_bc);
>> the input is timelock data with 306 channels and 801 timebins
>> applying preprocessing options
>> ??? Undefined function or method 'butter' for input arguments of type
>> 'double'.
>>
>> Error in ==> preproc_lowpassfilter at 80
>>    [B, A] = butter(N, max(Flp)/Fn);
>>
>> Error in ==> preproc at 360
>> if strcmp(cfg.lpfilter, 'yes'),     dat = preproc_lowpassfilter(dat,
>> fsample, cfg.lpfreq, cfg.lpfiltord,
>> cfg.lpfilttype, cfg.lpfiltdir); end
>>
>> Error in ==> timelockanalysis at 318
>>  [data.trial{i}, data.label, data.time{i}, cfg.preproc] =
>> preproc(data.trial{i}, data.label,
>>  data.fsample, cfg.preproc, data.offset(i));
>> =================================
>> %RESAMPLE
>> ??? Error: File: isequal.m Line: 1 Column: 1
>> The input character is not valid in MATLAB statements or expressions.
>>
>> Error in ==> checkdata at 145
>> if ~isequal(feedback, 'no')
>>
>> Error in ==> resampledata at 60
>> data = checkdata(data, 'datatype', 'raw', 'feedback', 'yes');
>>
>> =================================
>> The data structure looks fine to me:
>>
>> data_dev1 =
>>        hdr: [1x1 struct]
>>      label: {306x1 cell}
>>      trial: {1x101 cell}
>>       time: {1x101 cell}
>>    fsample: 1000
>>       grad: [1x1 struct]
>>        cfg: [1x1 struct]
>>
>> data_dev1.grad =
>>      pnt: [510x3 double]
>>      ori: [510x3 double]
>>      tra: [306x510 double]
>>     unit: 'cm'
>>    label: {1x306 cell}
>>
>>
>> Any idea on these error messages?
>>
>> 2. The second issue is that doing a timelockanalysis on these data
>> returns
>> no neg or pos clusters. There is no error message and the computations
>> seem
>> to run fine.
>>
>> Am I missing some steps in the preliminary stages of data analysis for
>> MEG
>> in fieldtrip?
>>
>> Thanks for any help you may provide,
>>
>> Virginie
>>
>> ----------------------------------
>> 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/fcdonders/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/fcdonders/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/fcdonders/fieldtrip.