[FieldTrip] different gradiometer-units from fiff-file
scho at med.ovgu.de
Wed Mar 8 17:52:46 CET 2017
My name is Michael Scholz and I am working in Magdeburg (Germany)
in the Department of Neurology.
We just started using our Elekta Neuromag Triux System.
I was going to use fieldtrip to create some simulation data to
test Elekta software. Therefore I read data from a fiff-file acquired
by the Elekta-MEG-system including 102 magnetometer-data and 2x102
Reading fiff-files with ft_read_data creates output with magnetometer-data
in Tesla (T) and gradiometer-data in T/m just as in the fiff-file.
Reading the same fiff-file by ft_read_sens creates a structure with
header-info including T/cm-unit-info for the gradiometer-sensors.
This was not expected and was misleading; if one doesnt recognize
these different units for the gradiometers and combines data based
on ft_read_sens-output and ft_read_data-output, the result is unusable,
since scaling of magnetometer-data and gradiometer-data wont match.
How can I prevent ft_read_sens from reading gradiometer in different
units as given in the source-fiff-file?
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