1## Copyright (C) 2021 David Legland
2## All rights reserved.
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27
28function lengths = grEdgeLengths(nodes, edges, varargin)
29%GREDGELENGTHS  Compute length of edges in a geometric graph.
30%
31%   LENGTHS = grEdgeLengths(NODES, EDGES)
32%
33%   Example
34%     % create a basic graph and display it
35%     nodes = [10 10;20 10;10 20;20 20;27 15];
36%     edges = [1 2;1 3;2 4;2 5;3 4;4 5];
37%     figure; drawGraph(nodes, edges);
38%     hold on; drawNodeLabels(nodes, 1:5)
39%     axis equal; axis([0 40 0 30]);
40%     % compute list of nodes adjacent to node with index 2
41%     grEdgeLengths(nodes, edges)'
42%     ans =
43%          10.0000   10.0000   10.0000    8.6023   10.0000    8.6023
44%
45%   See also
46%
47
48% ------
49% Author: David Legland
50% e-mail: david.legland@grignon.inra.fr
51% Created: 2014-01-13,    using Matlab 7.9.0.529 (R2009b)
52% Copyright 2014 INRA - Cepia Software Platform.
53
54nEdges = size(edges, 1);
55lengths = zeros(nEdges, 1);
56
57
58for iEdge = 1:nEdges
59    ed = edges(iEdge, :);
60    node1 = nodes(ed(1),:);
61    node2 = nodes(ed(2),:);
62    lengths(iEdge) = sqrt(sum((node1 - node2).^2));
63end
64