neuromag_load_meg_data

 load data from fiffile.
 [USAGE]
    [bexp] = neuromag_load_meg_data(<fif_file>, <index_in_fif_file>);
 [IN]
                  fif_file : fif file(Continuous file or Evoked file)
          index_in_fiffile : = -1 : continuous
                             =  N : read data set number in fiffile.
 [OUT]
    bexp : The data of one channel in each row, a single time sample in
           each column. Units: SI units. fT/m for gradiometers, fT for
           magnetometers, V for electric channels.

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

0001 function [bexp, ch_info, sf] = neuromag_load_meg_data(fif_file, index_in_fiffile)
0002 % load data from fiffile.
0003 % [USAGE]
0004 %    [bexp] = neuromag_load_meg_data(<fif_file>, <index_in_fif_file>);
0005 % [IN]
0006 %                  fif_file : fif file(Continuous file or Evoked file)
0007 %          index_in_fiffile : = -1 : continuous
0008 %                             =  N : read data set number in fiffile.
0009 % [OUT]
0010 %    bexp : The data of one channel in each row, a single time sample in
0011 %           each column. Units: SI units. fT/m for gradiometers, fT for
0012 %           magnetometers, V for electric channels.
0013 %
0014 % Copyright (C) 2011, ATR All Rights Reserved.
0015 % License : New BSD License(see VBMEG_LICENSE.txt)
0016 
0017 %
0018 % --- Previous check
0019 %
0020 if ~exist('fif_file', 'var')
0021     error('fif_file is a required parameter.');
0022 end
0023 if exist(fif_file, 'file') ~= 2
0024     error('fif_file:%s is not found.', fif_file);
0025 end
0026 if ~exist('index_in_fiffile', 'var')
0027     index_in_fiffile = -1; % continuous
0028 end
0029 
0030 
0031 %
0032 % --- Main Procedure
0033 %
0034 ch_info = neuromag_load_ch_info(fif_file);
0035 
0036 if index_in_fiffile == -1
0037     % load Continuous data
0038     raw  = fiff_setup_read_raw(fif_file);
0039     bexp = fiff_read_raw_segment(raw);
0040     sf   = raw.info.sfreq;
0041 else
0042     % load Evoked data
0043     raw  = fiff_read_evoked(fif_file, index_in_fiffile);
0044     bexp = raw.evoked.epochs;
0045     sf   = raw.info.sfreq;
0046 end
0047 
0048 meg_ix = [];
0049 for k=1:ch_info.Nch
0050     channel_name = ch_info.channel_name(k, :);
0051     meg_ix = [meg_ix; strmatch(channel_name, raw.info.ch_names, 'exact')];
0052 end
0053 bexp = bexp(meg_ix, :, :);