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: sn2individual.m
    path of file: ./repos/fieldtrip/utilities/private
    
    the code of the file until where you have to start completion: function [warped]= sn2individual(P, input)

% SN2INDIVIDUAL warps the input coordinates (defined as Nx3 matrix) from
% normalised MNI coordinates to individual headspace coordinates, using the
% warp parameters defined in the structure spmparams.
%
% this is modified from code from nutmeg: nut_mni2mri, which was itself
% modified from code originally written by John Ashburner:
% http://www.sph.umich.edu/~nichols/JG2/get_orig_coord2.m

% Copyright (C) 2013-2021, Jan-Mathijs Schoffelen
%
% 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 isfield(P, 'Tr')
  % this is an old-style representation of the parameters, so it uses the
  % code adjusted from nut_mni2mri
  
  if numel(P.Tr)==0
    % only an affine transformation has been done
    T      = P.VF.mat*P.Affine/(P.VG.mat);
    warped = ft_warp_apply(T, input);
    
  else
    % we need the spm_dctmtx function for the nonlinear case

    
function [warped]= sn2individual(P, input)

% SN2INDIVIDUAL warps the input coordinates (defined as Nx3 matrix) from
% normalised MNI coordinates to individual headspace coordinates, using the
% warp parameters defined in the structure spmparams.
%
% this is modified from code from nutmeg: nut_mni2mri, which was itself
% modified from code originally written by John Ashburner:
% http://www.sph.umich.edu/~nichols/JG2/get_orig_coord2.m

% Copyright (C) 2013-2021, Jan-Mathijs Schoffelen
%
% 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 isfield(P, 'Tr')
  % this is an old-style representation of the parameters, so it uses the
  % code adjusted from nut_mni2mri
  
  if numel(P.Tr)==0
    % only an affine transformation has been done
    T      = P.VF.mat*P.Affine/(P.VG.mat);
    warped = ft_warp_apply(T, input);
    
  else
    % we need the spm_dctmtx function for the nonlinear case
    if ~ft_hastoolbox('spm')
      % add SPM8 or later to the path
      ft_hastoolbox('spm8up', 1);
    end