Hi Akiko,
It is my understanding that if you start out with separate .fif files for
separate runs in MNE, you can never simply concatenate them into one long
run in MNE. You can combine them in other ways, by say creating separate
averages and then creating an average across runs, but of course that is
not going to be exactly equivalent.
As far as I can see, the only advantage to having separate .fif files for
separate runs is the benefit when you're recording of re-measuring and
attaching new head position coordinates to each run. But if you originally
recorded the data as one long .sqd file so that you won't get that benefit
anyway, I think you're much better off converting it to a single .fif
file.
Something I have been doing to get around the huge filesize problem in the
KIT->MNE conversion is to epoch the data first and then convert the
epoched file to MNE. The only thing to be careful about that is that you
filter either before that step or wait and filter after you average.
Ellen
Today's Topics:
1. concatenate data from multiple runs (Akiko Ikkai)
----------------------------------------------------------------------
Message: 1
Date: Wed, 07 Apr 2010 21:50:18 -0400
From: Akiko Ikkai <akiko at nyu.edu>
Subject: [Mne_analysis] concatenate data from multiple runs
To: mne_analysis at nmr.mgh.harvard.edu
Message-ID: <5fd0f2401551e4.4bbcfe1a at mail.nyu.edu>
Content-Type: text/plain; charset=us-asciiHi,
I'm very new to MNE, and have a quick question. My MEG experiment has 5
runs, each of which is 5 min. We are using KIT system, and I could feed
a
huge ascii file to mne-kit2fif, but I'm wondering if there is an
alternative way to concatenate runs after this conversion (convert each
run to .fif separately), perhaps right before offline averaging? I was
browsing the manual, but could not find a section on this topic.