Kambiz Tavabi kambiz.tavabi at UNI-MUENSTER.DE
Fri Feb 17 11:13:15 CET 2006

Hi Jan,

When it comes to MATLAB I am a low level kind of guy!

With a break @ line 64
>stim =  read_ctf_meg4(datafile, hdr, 1, hdr.nTrials*hdr.nSamples,
A call to stimindx returns; Empty matrix: 0-by-1.

The data I have has been recorded on a CTF machine with the newest available
software which apparently displays only a virtual channel labeled STIM seen
in the Data Editor.  The virtual STIM channel is a combination of UPPT01 &
UPPT02 parallel ports used for stimulus delivery.  I can send you the dsinfo
for this file if you'd like.

Apparently stimindx is empty; and my dataset consists of a no channel
labeled STIM.  But this is in accordance with current CTF format.  What to
do now?


-----Original Message-----
From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On Behalf
Of Jan Mathijs Schoffelen
Sent: Friday, February 17, 2006 10:18 AM
Subject: Re: [FIELDTRIP] wavelet analysis

Dear Kambiz,

This looks like a pretty low level error to me.

>??? Error using ==> fieldtrip-20060131\private\read_ctf_meg4
>no channels were specified for reading CTF data

>Error in ==> fieldtrip-20060131\private\read_ctf_trigger at 64
>stim =  read_ctf_meg4(datafile, hdr, 1, hdr.nTrials*hdr.nSamples,

It seems as if the variable stimindx has not been defined. Perhaps you could
check that first, by putting a breakpoint at the specified line in

Might it be the case that your dataset does not contain a channel with the
label 'STIM'?

Yours, Jan-Mathijs

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