graphDiameter

GRAPHDIAMETER Diameter of a graph.

   D = graphDiameter(V, E)
   Computes the diameter of the graph given by V and E. The diameter of
   the graph is the greatest eccentricity over all vertices in the graph.

   D = graphDiameter(V, E, L)
   Specifies the weight of each edge for computing the distances. Default
   is to consider a weight of 1 for each edge.

   Example
     nodes = [20 20;20 50;20 80;50 50;80 20;80 50;80 80];
     edges = [1 2;2 3;2 4;4 6;5 6;6 7];
     figure; drawGraph(nodes, edges);
     axis([0 100 0 100]); axis equal; hold on
     D = graphDiameter(nodes, edges)
     D = 
         4

   See also
   grPropagateDistance, grVertexEccentricity
   graphCenter, graphRadius, graphPeripheralVertices

0001 function diam = graphDiameter(v, e, l)
0002 %GRAPHDIAMETER Diameter of a graph.
0003 %
0004 %   D = graphDiameter(V, E)
0005 %   Computes the diameter of the graph given by V and E. The diameter of
0006 %   the graph is the greatest eccentricity over all vertices in the graph.
0007 %
0008 %   D = graphDiameter(V, E, L)
0009 %   Specifies the weight of each edge for computing the distances. Default
0010 %   is to consider a weight of 1 for each edge.
0011 %
0012 %   Example
0013 %     nodes = [20 20;20 50;20 80;50 50;80 20;80 50;80 80];
0014 %     edges = [1 2;2 3;2 4;4 6;5 6;6 7];
0015 %     figure; drawGraph(nodes, edges);
0016 %     axis([0 100 0 100]); axis equal; hold on
0017 %     D = graphDiameter(nodes, edges)
0018 %     D =
0019 %         4
0020 %
0021 %   See also
0022 %   grPropagateDistance, grVertexEccentricity
0023 %   graphCenter, graphRadius, graphPeripheralVertices
0024 %
0025 
0026 % ------
0027 % Author: David Legland
0028 % E-mail: david.legland@inrae.fr
0029 % Created: 2010-09-07, using Matlab 7.9.0.529 (R2009b)
0030 % Copyright 2010-2024 INRA - Cepia Software Platform
0031 
0032 % ensure there is a valid length array
0033 if nargin<3
0034     l = ones(size(e,1), 1);
0035 end
0036 
0037 g = grVertexEccentricity(v, e, l);
0038 
0039 diam = max(g);