MATLAB: How to find maximum eccentricity of a vertex of non-directed graph

eccentricity

How to find maximum eccentricity of a vertex of non-directed graph?

Best Answer

%need a graph
s = [1 1 2 3 3 4 4 6 6 7 8 7 5];
t = [2 3 4 4 5 5 6 1 8 1 3 2 8];
G = digraph(s,t);
%now process it
allnodes = unique(G.Edges.EndNodes);
numnodes = length(allnodes);
eccentricities = zeros(1, numnodes);
for N = 1 : numnodes
  thisnode = allnodes(N);
  [~, D] = shortestpathtree(G,thisnode);
  eccentricities(N) = max(D);
end
graph_diameter = max(eccentricities);

Related Solutions

MATLAB: Is it possible to remove labels added with labelnode

Here's how to remove all labels and how to restore default labels

% Create demo GraphPlot
s = [1 1 2 2 3 4 5 5];
t = [2 3 3 4 4 5 1 2];
G = digraph(s,t);
h = plot(G); % Store handle!
labelnode(h,[1 2],{'source' 'target'})
% To reset labels
h.NodeLabelMode = 'auto'; 
% To remove all labels
h.NodeLabel = {};

MATLAB: Determine separated node in graph

I'm not sure what is the final goal and/or application of this process. But let me try to do this task (since this "puzzle" will be a good excerise for me!)

% Create Graph object with fixed node name
s = [1 2 2 4 5 4 8 7 7 8 13];
t = [3 3 11 5 6 6 7 10 12 12 9];
G = graph(s,t,[],compose('%d',1:13));
% Separate G to subgraphs
group = conncomp(G,'OutputForm','cell');
subGraph = cellfun(@(x) subgraph(G,x),group,'UniformOutput',false);
% Initialize the output cell array (= result)
C_out = cell(1,numel(subGraph));
for kk1 = 1:numel(subGraph)
  % kk1-th subgraph
  G = subGraph{kk1};
  nodes = G.Nodes.Name';
  c = cell(1,numel(nodes));
  % Find non-neighbouring nodes for each node and create the output cell
  % arrray for each subgraph
  for kk2 = 1:numel(nodes)
    nextNodes = neighbors(G,nodes{kk2})';
    nonNextNodes = setdiff(nodes,[nodes(kk2),nextNodes]);
    if isempty(nonNextNodes)
      c{kk2} = str2double(nodes(kk2));
    else
      [~,pt] = sort(str2double(nonNextNodes));
      c{kk2} = str2double(nonNextNodes(pt));
    end
  end
  
  % Store the result for each subgraph
  C_out{kk1} = c;
end

Best Answer

Related Solutions

MATLAB: Is it possible to remove labels added with labelnode

MATLAB: Determine separated node in graph

Related Question