You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spm_eeg_artefact_threshchan.m
    path of file: ./repos/spm
    
    the code of the file until where you have to start completion: function res = spm_eeg_artefact_threshchan(S)
% Plugin for spm_eeg_artefact doing artefact detection by channel thresholding
% S            - input structure
% fields of S:
%    S.D       - M/EEG object
%    S.chanind - vector of indices of channels that this plugin will look at
%                         
%    Additional parameters can be defined specific for each plugin.
%
% Output:
% res - 
%    If no input is provided the plugin returns a cfg branch for itself.
%
%    If input is provided the plugin returns a matrix of size D.nchannels x D.ntrials  
%    with zeros for clean channel/trials and ones for artefacts.
%__________________________________________________________________________

% Vladimir Litvak
% Copyright (C) 2008-2022 Wellcome Centre for Human Neuroimaging


%-This part if for creating a config branch that plugs into spm_cfg_eeg_artefact
% Any parameters can be specified and they are then passed to the plugin
% when it's called.
%--------------------------------------------------------------------------
if nargin == 0
    threshold         = cfg_entry;
    threshold.tag     = 'threshold';
    threshold.name    = 'Threshold';
    threshold.strtype = 'r';
    threshold.num     = [1 1];
    threshold.help    = {'Threshold value to apply to all channels.'};

    excwin         = cfg_entry;
    excwin.tag     = 'excwin';
    excwin.name    = 'Excision window';
    excwin.strtype = 'r';
    excwin.num     = [1 1];
    excwin.val     = {1000};
    excwin.help    = {'Window (in ms) to mark as bad around each jump (for mark mode only), 0 - do not mark data as bad.'};
    
    

    
function res = spm_eeg_artefact_threshchan(S)
% Plugin for spm_eeg_artefact doing artefact detection by channel thresholding
% S            - input structure
% fields of S:
%    S.D       - M/EEG object
%    S.chanind - vector of indices of channels that this plugin will look at
%                         
%    Additional parameters can be defined specific for each plugin.
%
% Output:
% res - 
%    If no input is provided the plugin returns a cfg branch for itself.
%
%    If input is provided the plugin returns a matrix of size D.nchannels x D.ntrials  
%    with zeros for clean channel/trials and ones for artefacts.
%__________________________________________________________________________

% Vladimir Litvak
% Copyright (C) 2008-2022 Wellcome Centre for Human Neuroimaging


%-This part if for creating a config branch that plugs into spm_cfg_eeg_artefact
% Any parameters can be specified and they are then passed to the plugin
% when it's called.
%--------------------------------------------------------------------------
if nargin == 0
    threshold         = cfg_entry;
    threshold.tag     = 'threshold';
    threshold.name    = 'Threshold';
    threshold.strtype = 'r';
    threshold.num     = [1 1];
    threshold.help    = {'Threshold value to apply to all channels.'};

    excwin         = cfg_entry;
    excwin.tag     = 'excwin';
    excwin.name    = 'Excision window';
    excwin.strtype = 'r';
    excwin.num     = [1 1];
    excwin.val     = {1000};
    excwin.help    = {'Window (in ms) to mark as bad around each jump (for mark mode only), 0 - do not mark data as bad.'};
    
    
    threshchan      = cfg_branch;
    threshchan.tag  = 'threshchan';
    threshchan.name = 'Threshold channels';
    threshchan.val  = {threshold, excwin};
    threshchan.help = {''};
    
    res = threshchan;
    
    return
end