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    Metadata details:
    filename: ft_channelcombination.m
    path of file: ./repos/fieldtrip/utilities
    
    the code of the file until where you have to start completion: function [collect] = ft_channelcombination(channelcmb, datachannel, includeauto, dirflag)

% FT_CHANNELCOMBINATION creates a cell-array with combinations of EEG/MEG channels
% for subsequent cross-spectral-density, coherence and/or connectivity ananalysis
%
% You should specify channel combinations as a two-column cell-array,
%   cfg.channelcmb = {  'EMG' 'MLF31'
%                       'EMG' 'MLF32'
%                       'EMG' 'MLF33' };
% to compare EMG with these three sensors, or
%   cfg.channelcmb = { 'MEG' 'MEG' };
% to make all MEG combinations, or
%   cfg.channelcmb = { 'EMG' 'MEG' };
% to make all combinations between the EMG and all MEG channels.
%
% For each column, you can specify a mixture of real channel labels
% and of special strings that will be replaced by the corresponding
% channel labels. Channels that are not present in the raw datafile
% are automatically removed from the channel list.
%
% When directional connectivity measures will subsequently be computed, the
% interpretation of each channel-combination is that the direction of the
% interaction is from the first column to the second column.
%
% Note that the default behavior is to exclude symmetric pairs and
% auto-combinations.
%
% See also FT_CHANNELSELECTION

% Undocumented options:

    
function [collect] = ft_channelcombination(channelcmb, datachannel, includeauto, dirflag)

% FT_CHANNELCOMBINATION creates a cell-array with combinations of EEG/MEG channels
% for subsequent cross-spectral-density, coherence and/or connectivity ananalysis
%
% You should specify channel combinations as a two-column cell-array,
%   cfg.channelcmb = {  'EMG' 'MLF31'
%                       'EMG' 'MLF32'
%                       'EMG' 'MLF33' };
% to compare EMG with these three sensors, or
%   cfg.channelcmb = { 'MEG' 'MEG' };
% to make all MEG combinations, or
%   cfg.channelcmb = { 'EMG' 'MEG' };
% to make all combinations between the EMG and all MEG channels.
%
% For each column, you can specify a mixture of real channel labels
% and of special strings that will be replaced by the corresponding
% channel labels. Channels that are not present in the raw datafile
% are automatically removed from the channel list.
%
% When directional connectivity measures will subsequently be computed, the
% interpretation of each channel-combination is that the direction of the
% interaction is from the first column to the second column.
%
% Note that the default behavior is to exclude symmetric pairs and
% auto-combinations.
%
% See also FT_CHANNELSELECTION

% Undocumented options:
%   includeauto = 0 (or 1), include auto-combinations
%   dirflag     = 0 (or 1, or 2) specifies the treatment of the order in
%                   the columns of the output. If dirflag = 0, the order is
%                   preserved, if dirflag = 1, the order is reversed,
%                   second input column is put first. If dirflag = 2, both
%                   directions are added to the list of combinations.

% Copyright (C) 2003-2015, Jan-Mathijs Schoffelen & Robert Oostenveld
%
% This file is part of FieldTrip, see http://www.fieldtriptoolbox.org
% for the documentation and details.
%
%    FieldTrip is free software: you can redistribute it and/or modify
%    it under the terms of the GNU General Public License as published by
%    the Free Software Foundation, either version 3 of the License, or
%    (at your option) any later version.
%
%    FieldTrip is distributed in the hope that it will be useful,
%    but WITHOUT ANY WARRANTY; without even the implied warranty of
%    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%    GNU General Public License for more details.
%
%    You should have received a copy of the GNU General Public License
%    along with FieldTrip. If not, see <http://www.gnu.org/licenses/>.
%
% $Id$

if nargin<3 || isempty(includeauto), includeauto = 0; end