1## Copyright (C) 2021 David Legland
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27
28function average = pointSetsAverage(pointSets, varargin)
29%POINTSETSAVERAGE Compute the average of several point sets.
30%
31%   AVERAGESET = pointSetsAverage(POINTSETS)
32%   POINTSETS is a cell array containing several liste of points with the
33%   same number of points. The function compute the average coordinate of
34%   each vertex, and return the resulting average point set.
35%
36%   Example
37%   pointSetsAverage
38%
39%   See also
40%
41%
42% ------
43% Author: David Legland
44% e-mail: david.legland@grignon.inra.fr
45% Created: 2011-04-01,    using Matlab 7.9.0.529 (R2009b)
46% Copyright 2011 INRA - Cepia Software Platform.
47
48% check input
49if ~iscell(pointSets)
50    error('First argument must be a cell array');
51end
52
53% number of sets
54nSets   = length(pointSets);
55
56% get reference size of coordinates array
57set1    = pointSets{1};
58refSize = size(set1);
59
60% allocate memory for result
61average = zeros(refSize);
62
63% iterate on point sets
64for i = 1:nSets
65    % get current point set, and check its size
66    set = pointSets{i};
67    if sum(size(set) ~= refSize) > 0
68        error('All point sets must have the same size');
69    end
70
71    % cumulative sum of coordinates
72    average = average + set;
73end
74
75% normalize by the number of sets
76average = average / nSets;
77