[FieldTrip] ft_prepare_vol_sens-missing .mat file

[IMALI THANUJA HETTIARACHCHI]

Dear fieldtrip users,

I am using a BEM (using OPENMEEG) created volume conduction model, and in order to  prepare lead fields I loaded the electrode array with,
elec = ft_read_sens('mydirectory\standard_1020.elc');

The I used the function,

[vol, sens] = ft_prepare_vol_sens(vol, elec);
However this give as error,

??? Reference to non-existent field 'mat'.

Error in ==> ft_prepare_vol_sens at 419
        if size(vol.mat,1)~=size(vol.mat,2) && size(vol.mat,1)==length(sens.elecpos)

Error in ==> curry_leadField at 15
  [vol, sens] = ft_prepare_vol_sens(vol, elec);

The vol created with the OPENMEEG only contains the following fields,
vol =

             bnd: [1x3 struct]
            cond: [0.3300 0.0042 0.3300]
    skin_surface: 1
          source: 3
            type: 'openmeeg'
            unit: 'mm'
            cfg: [1x1 struct]

Can someone please help me with this error, any advice and comment will be highly appreciated.
Thank you very much!

Regards
Imali

Imali Thanuja Hettiarachchi
PhD Candidate
Centre for Intelligent Systems research
Deakin University, Geelong 3217, Australia.

Mobile : +61430321972
Email: ith at deakin.edu.au<mailto:ith at deakin.edu.au>
www.deakin.edu.au/cisr<http://www.deakin.edu.au/cisr>

[Description: Description: Description: cid:1216BE20-1800-4A47-8B9F-E7B9D94831CD at deakin.edu.au]




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