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: evaluation_ev_image.m
    path of file: ./repos/extended-berkeley-segmentation-benchmark/benchmarks
    
    the code of the file until where you have to start completion: function [sumSuperpixelVariation, sumOverallVariation] = evaluation_ev_image(inFile, gtFile, imgFile, evFile10)
% function [sumSuperpixelVariation, sumOverallVariation] = evaluation_ev_image(inFile, gtFile, imgFile, evFile10)
%
% Calculates Explained Variation as described in [1]:

    
function [sumSuperpixelVariation, sumOverallVariation] = evaluation_ev_image(inFile, gtFile, imgFile, evFile10)
% function [sumSuperpixelVariation, sumOverallVariation] = evaluation_ev_image(inFile, gtFile, imgFile, evFile10)
%
% Calculates Explained Variation as described in [1]:
%
%   [1] D. Tang, H. Fu, and X. Cao.
%       Topology preserved regular superpixel.
%       In Multimedia and Expo, International Conference on, pages 765â€“768, Melbourne, Australia, July 2012
%
% INPUT
%	inFile:     a collection of segmentations in a cell 'segs' stored in a mat file
%               - note that using an ultrametric contour map is not possible
%               with this evaluation function.
%	gtFile:     file containing a cell of ground truth segmentations
%   imgFIle:    correpsonding image
%   evFile10:   temporary output for this image
%
% OUTPUT
%	sumSuperpixelVariation: nominator of explained variation
%   sumOverallVariation:    denominator of explained variation
%
% David Stutz <david.stutz@rwth-aachen.de>

    load(inFile); 

    % Only run if we have the correct format - does not work on ucm
    if exist('segs', 'var')

        load(gtFile);
        nSegs = numel(groundTruth);
        if nSegs == 0,
            error('bad gtFile!');
        end