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Bug 2549 - test_ft_channelselection fails

Reported 2014-04-30 09:36:00 +0200
Modified 2014-05-14 20:08:57 +0200
Product: FieldTrip
Component: test
Version: unspecified
Hardware: PC
Operating System: Windows
Importance: P5 normal
Assigned to: Robert Oostenveld
Depends on:
See also:

Jörn M. Horschig - 2014-04-30 09:36:08 +0200

neuroscan16 data has numeeg 58, but channelselection only finds 53 EEG channels. The reason for that is because of wrong/strange labels in the neuroscan data. For example, there are electrodes labelled as T3 and T4, which do not exist according to the common 10-10 convention. Other electrodes are called e.g. 'AF7 L', which should probably mark the left EOG channel. The dataset has 64 channels in total, two are labelled as free, two other probably as eog, and two others probably as ground and reference, which would make in total 58 electrodes. But then there are also the 'T*' elecs which do not exist and 'A2', which result in 53 detected channels

Robert Oostenveld - 2014-04-30 12:58:37 +0200

The T electrodes are temporal according to the old nomenclature. T3 and T4 are above the ear, T5 and T6 a bit further back. These are to be considered known EEG electrodes. The A1 and A2 are the earlobe electrodes, and should also be identified as EEG in case the data uses some sort of 1020 nomenclature. The 'AF7 L' is not a known electrode location according to the old or new 1020/1010/1005 nomenclature and should not be identified as EEG.

Jörn M. Horschig - 2014-04-30 13:02:15 +0200

then it's probably an error in the test script, because it wants to match electrode labels with the eeg1010 labels, which is not a wise idea?

Robert Oostenveld - 2014-04-30 15:38:02 +0200

it might be that the error in the test script relates to the changes for bug 2463. see also

Robert Oostenveld - 2014-05-01 17:52:46 +0200

I added {'A1' 'A2' 'M1' 'M2' 'T3' 'T4' 'T5' 'T6'} to the eeg1020 eeg1010 and eeg105 specification in ft_senslabel. It was already there for the ext1020 specification. That solves the problem for test case 4 in the test scrip. But subsequently it gets stuck on Error using test_ft_channelselection (line 21) incorrect senstype detection: neuroscan32 K>> i i = 5 K>> datasets(i) ans = origdir: '/home/common/matlab/fieldtrip/data/test/' type: 'eeg' datatype: 'neuroscan32' filename: 'Subject1_MP.cnt' numeeg: 62 nummeg: NaN numeog: NaN numecg: NaN numemg: NaN senstype: 'ext1020' dataformat: [] nummegmag: [] nummeggrad: []

Robert Oostenveld - 2014-05-01 18:00:52 +0200

the other problem was easy to resolve. mac011> svn commit forward/ ft_channelselection.m test/ Sending forward/ft_senslabel.m Sending forward/ft_senstype.m Sending ft_channelselection.m Sending test/test_ft_channelselection.m Transmitting file data .... Committed revision 9461.

Robert Oostenveld - 2014-05-14 20:08:57 +0200

closed several of my bugs that have been resolved