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An error during a P300 calibration session

Posted: 07 Jun 2011, 14:48
by shalala
Hi,

I followed the P300 tutorial to perform P300 experiment using Emotiv Epoc headset on Windows 7 64 bits.

The calibration session went smoothly until when I created a subject-specific parameter file. After I set the matrix for Classifier using 4 values obtained from the previous offline analysis plot, I got this error when I tried to start the experiment again:

LinearClassifier::Preflight: Channel specification in
Classifier(1,input channel)=8
exceeds number of input channels.

Warning: LinearClassifier::Preflight: Specification in physical units:
Classifier(1,input element (bin))=472.7ms
does not exactly meet a single element.


I thought the number of input channels is 14, so I don't know why 8 would exceed number of input channels.

Thank you very much for your help.

Re: An error during a P300 calibration session

Posted: 08 Jun 2011, 09:11
by mellinger
Hi,

the error message refers to the number of input channels to the LinearClassifier filter, not the number of recorded channels.
The number of channels actually transmitted to the LinearClassifier depends on the TransmitChList parameter. You should list all recorded channels there, from 1 to 14 to have them available for classification.

Thanks for pointing this out, I'll add a note to the wiki about the TransmitChList parameter.

Regards,
Juergen

Re: An error during a P300 calibration session

Posted: 08 Jun 2011, 20:05
by shalala
Thank you very much! It works perfectly now. :D