multiplotER and Neuromag data

Gianpaolo Demarchi gianpaolo.demarchi at UNITN.IT
Wed Feb 24 15:06:25 CET 2010

Dear Stephan,
thanks for your 'patch' !
It works, i.e. I get a multiplotER graph with some data in it!
With "your version" at least we get back a multiplot, with sadly the
gradiometers and magnetometers data overlapped. The 'old' way was plotting
them arranged in triplets, with one magnetometer and the two gradiometers
'clustered' together. I checked the 'old' prepare_layout.m, and in fact in the
grad2lay() function  there was a 'finer grained' check of the sensor type,
including 	a different/better layout for 'neuromag306' case.
Anyway, there must be a reason for choosing this option (probably the old
arrangement with mag+2grads sublopts was too crowded, and probably useless),
and in case we can still make two different multiplotERs for magnetometers and
gradiometers ...
Thanks again,

PS: should this one be considered a 'patch' for a 'bug', and go upstream in
the official  fieldtrip release?

> I had the same problem as you. The probel lies in the ft_prepare_layout.m
> function. It calculates the minimum distance between sensors. As the
> neuromag sensor has different types of sensors, the layout puts the 3
> different sensors at the same place. So calculating the min(d(:)) results
> in 0 values. Please find below the modified subfunction sens2lay that is
> located in ft_prepare_layout.m that prevents this error. With that, the
> topoplots (and multiplots) should work out. Maybe this error can be
> prevented in a more elegant way that I did.
> Best,
> Stephan

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