forming one datset from multiple data files

David Ziegler daz at MIT.EDU
Wed Apr 14 21:19:32 CEST 2010

Hi Fieldtrippers,

I have a similar situation where I have 3 "runs" of trials that were
collected separately on a neuromag306 system.  I took Ingrid's advice and
ran ft_appenddata on my preprocessed (e.g., trigger-based trial selection,
artifact rejection, and preprocessing) data files to combine the three
datasets into a single file.  The function worked, but with the warning that
the sensor info was not consistent across trials:

>> cfg=[];
>> allT4 = ft_appenddata(cfg, dataT4_list11, dataT4_list8, dataT4_list9);
input dataset 1, 308 channels, 32 trials
input dataset 2, 308 channels, 32 trials
input dataset 3, 308 channels, 32 trials
Warning: sensor information does not seem to be consistent across the input
> In ft_appenddata at 106
concatenating the trials over all datasets
removing sensor information from output
output dataset, 308 channels, 96 trials

Is there a better way to concatenate several runs of similar trials such
that the sensor information is preserved?  I can generate an time-locked
average on the resulting concatenated data, but I am not able to plot it
using multiplot or topoplot, just by viewing individual single channels
(presumably due to the stripping of the sensory info).

Thanks for any advice!

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