vb_megfile_write_pretrigger

 Overwrite pretrigger of MEG data
 [usage]
   vb_megfile_write_pretrigger(megfile, pretrigger)
 [input]
      megfile : <required> <<file>> .meg.mat file as base and this is updated
   pretrigger : <required> pretrigger
 [output]
   none
 [note]
   If the given megfile has old fashioned field name, 
   this function replaces it with new one.
 --- History
 2008-12-04 Taku Yoshioka
 2010-01-19 (Sako) replaced vb_load_meg_info with vb_load_measurement_info
 2010-01-26 (Sako) rename

 Copyright (C) 2011, ATR All Rights Reserved.
 License : New BSD License(see VBMEG_LICENSE.txt)

0001 function vb_megfile_write_pretrigger(megfile, pretrigger)
0002 % Overwrite pretrigger of MEG data
0003 % [usage]
0004 %   vb_megfile_write_pretrigger(megfile, pretrigger)
0005 % [input]
0006 %      megfile : <required> <<file>> .meg.mat file as base and this is updated
0007 %   pretrigger : <required> pretrigger
0008 % [output]
0009 %   none
0010 % [note]
0011 %   If the given megfile has old fashioned field name,
0012 %   this function replaces it with new one.
0013 % --- History
0014 % 2008-12-04 Taku Yoshioka
0015 % 2010-01-19 (Sako) replaced vb_load_meg_info with vb_load_measurement_info
0016 % 2010-01-26 (Sako) rename
0017 %
0018 % Copyright (C) 2011, ATR All Rights Reserved.
0019 % License : New BSD License(see VBMEG_LICENSE.txt)
0020 
0021 MEGinfo = vb_load_measurement_info(megfile);
0022 if isfield(MEGinfo,'Pretriger'), 
0023   MEGinfo = rmfield(MEGinfo,'Pretriger'); 
0024 end
0025 MEGinfo.Pretrigger = pretrigger;
0026 vb_save(megfile,'MEGinfo');