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_summarise.m
    path of file: ./repos/malini/Codes/deconvolution - model/spm8
    
    the code of the file until where you have to start completion: function [Y, xY] = spm_summarise(V,xY,fhandle,keepNaNs)
% Summarise data within a Region of Interest
% FUNCTION [Y, xY] = spm_summarise(V,xY,fhandle)
% V       - [1 x n] vector of mapped image volumes to read (from spm_vol)
% xY      - VOI structure (from spm_ROI)
%           Or a VOI_*.mat (from spm_regions) or a mask image filename
%           Or the keyword 'all' to summarise all voxels in the images
%           Or a [3 x m] matrix of voxel coordinates {mm}
% fhandle - function handle to be applied on image data within VOI
%           Must transform a [1 x m] array into a [1 x p] array
%           Default is Identity (returns raw data, vectorised into rows)
%

    
function [Y, xY] = spm_summarise(V,xY,fhandle,keepNaNs)
% Summarise data within a Region of Interest
% FUNCTION [Y, xY] = spm_summarise(V,xY,fhandle)
% V       - [1 x n] vector of mapped image volumes to read (from spm_vol)
% xY      - VOI structure (from spm_ROI)
%           Or a VOI_*.mat (from spm_regions) or a mask image filename
%           Or the keyword 'all' to summarise all voxels in the images
%           Or a [3 x m] matrix of voxel coordinates {mm}
% fhandle - function handle to be applied on image data within VOI
%           Must transform a [1 x m] array into a [1 x p] array
%           Default is Identity (returns raw data, vectorised into rows)
%
% Y       - [n x p] data summary
% xY      - (updated) VOI structure
%__________________________________________________________________________
% Copyright (C) 2010 Wellcome Trust Centre for Neuroimaging

% Guillaume Flandin, Ged Ridgway
% $Id: spm_summarise.m 4013 2010-07-22 17:12:45Z guillaume $

%-Argument checks
%--------------------------------------------------------------------------
if nargin < 1 || isempty(V)
    [V ok] = spm_select([1 Inf], 'image', 'Specify Images');
    if ~ok, error('Must select 1 or more images'), end