EEG-Recording in two separate files

Hi guys! I'm a MatLab beginner and have some question about sticking together two files, two "matrizes": I recorded an EEG in two parts because the programm failed in the middle of the measure. So now I have two .vhdr, .vmrk, .eeg-files, named X and X_two. Two preprocess them with Fieldtrip I need two stick them to another matrix which contains the Protocol of the measure. (.mat-file) Does anybody know how to stick X and X_two together but keep the .vhdr etc. endings? When I stick them together by the cat(dim,A,B)-Function (which works) I can save the "new" file as a binary .mat-file but not with the "original" endings. But to analyze the data I need the correct endings. Does anybody know help? If this comment is already there just link it down below please! PS: Excuse my incorrect English! I hope you pretty understood! Tanks

Answer 1

[Daniel M]

You shouldn't try to simply concatenate them in time because there will be a discontinuity between the end of the first dataset and the beginning of the second dataset. What you can do, if you're using fieldtrip, is to append them as two different trials (it's ok if they're different length).

Use the function ft_appenddata() to do this. It has different behaviour depending on if the channels between the two datasets are the same or not. If you need to save them back to their native file formats, you can then use ft_write_data() to do this.