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: pop_smootherp.m
    path of file: ./repos/erplab/pop_functions
    
    the code of the file until where you have to start completion: % PURPOSE  : Smooth ERP data (ERPLAB ERP structure)
%
% FORMAT   :
%
% ERP = pop_smootherp(ERP, npoints, stype);
%
% INPUTS     :
%
%         ERP              - ERP structures (ERPset)
%         npoints          - odd number of points.
%         stype            - 0=Savitzky-Golay smoothing filter
%                            1=moving average filter method
%
%
% OUTPUTS
%
%         ERP              - smoothed ERP data
%
%
% EXAMPLE 1 : Smooth the data using a 11 points Savitzky-Golay smoothing filter.
%
% ERP = pop_smootherp(ERP, 11, 1);
%
% EXAMPLE 2 : Smooth the data using a 7 points moving average filter method.
%
% ERP = pop_smootherp(ERP, 7, 0);
%
% See also smootherp.m smootherp2.m smooth.m sgolayfilt.m
%
% *** This function is part of ERPLAB Toolbox ***
% Author: Javier Lopez-Calderon
% Center for Mind and Brain
% University of California, Davis,
% Davis, CA
% 2012

%b8d3721ed219e65100184c6b95db209bb8d3721ed219e65100184c6b95db209b
%

    
function is part of ERPLAB Toolbox ***
% Author: Javier Lopez-Calderon
% Center for Mind and Brain
% University of California, Davis,
% Davis, CA
% 2012

%b8d3721ed219e65100184c6b95db209bb8d3721ed219e65100184c6b95db209b
%
% ERPLAB Toolbox
% Copyright © 2007 The Regents of the University of California
% Created by Javier Lopez-Calderon and Steven Luck
% Center for Mind and Brain, University of California, Davis,
% javlopez@ucdavis.edu, sjluck@ucdavis.edu
%
% This program 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.
%
% This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

function [ERP, erpcom] = pop_smootherp(ERP, npoints, stype)
erpcom = '';
if nargin < 1
      help pop_smootherp
      return
end