ft_channelrepair produces only NaNs

[Henning Holle]

Dear list members,

we have a data set here with a bad data channel (F8, see attached screenshot from the 
databrowser). 


we are able to read in the dataset (which was created in EEGLAB) and the electrode 
positions using the following code.

%% read in data

cfg = [];
cfg.dataset = 's29dr.set';
D = ft_preprocessing(cfg);
D.elec = D.hdr.elec;

however, when we want to interpolate the bad channel using the following code

%% interpolate bad channel F8

cfg = [];
cfg.badchannel     = 14;
E = ft_channelrepair(cfg,D);

we only have NaNs for channel 14

>> E.trial{1,1}(14,1:10)

ans =

   NaN   NaN   NaN   NaN   NaN   NaN   NaN   NaN   NaN   NaN

What are we doing wrong? One possibility that we have considered is that the electrode 
positions (which were obtained in EEGLAB) might be in a slightly different format than 
fieldtrip would expect them. We can't see anything wrong with, but we have attached a 
copy of the elec field here, just to be sure.

Or is it maybe a problem for the interpolation algorithm that F8 is at the edge of covered 
electrodes?

Any help would be greatly appreciated.

Kind regards,

Tiina Kalda and Henning Holle

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