Nodes belongto which Graph?

Dear matlab,

Please let me know if we can findout from the graph table which nodes belong to which graph, as in G.Edges in the graph function only shows connected nodes and linkages and weights, i.e node1 node2 weight

Can we have information that shows node and graph it belongs to, ex node1 graph1 node2 graph1 node3 graph2 node4 graph2 node5 graph2 node6 graph3

[Walter Roberson]

Did you perhaps want to ask about which vertices belong to which subgraph?

[Eng. Fredius Magige]

Hi An adjacency matrix (table) is pure a node to node connection. Either, movement of: TOP to RIGHT to TOP to RIGHT ..... or others are generated graphical model. whatever you want, it scientifically possible to get

Answer 1

[Walter Roberson]

If you have a series of graphs, G1, G2, G3, ... each of which has been created with graph(), or digraph() then:

Graphs = {G1, G2, G3, ... };     %create a cell array of all of the graphs
GraphNames = {'graph1', 'graph2', 'G3', ...};  %names of graphs to use in report

numgraph = length(Graphs);
nodes_are_numeric = false(numgraph, 1);
for K = 1 : numgraph
  these_nodes = unique(Graphs{K}.Edges.EndNodes(:));
  if ~iscell(these_nodes); these_nodes = num2cell(these_nodes); end
  used_nodes{K} = these_nodes;
  nodes_are_numeric(K) = isnumeric(these_nodes{1});
end

node_fmt_is_char = ~all(nodes_are_numeric);

if all(nodes_are_numeric) ~= any(nodes_are_numeric)
  %there is a mix of node types, need to convert the numeric ones to character
  for K = find(nodes_are_numeric(:)).'
    used_nodes{K} = cellfun(@num2str, used_nodes{K}, 'Uniform', 0);
  end
end

unique_nodes = unique( vertcat(used_nodes{:}) );

num_unique_nodes = length(unique_nodes);
node_belongs_to = cell(num_unique_nodes, 1);
for K = 1 : num_unique_nodes
  this_node = unique_nodes{K};
  node_is_in_graph = cellfun(@(N) ismember(this_node, N), used_nodes);
  node_member_of = GraphNames(node_is_in_graph);
  node_belongs_to{K} = [{this_node}, node_member_of];
end

%now the printed report
if node_fmt_is_char
  fmt = 'Node %s belongs to graphs: ';
else
  fmt = 'Node %g belongs to graphs: ';
end

for K = 1 : num_unique_nodes
  this_entry = node_belongs_to{K};
  fprintf(fmt, this_entry{1});
  fprintf('%s, ', this_entry{2:end} );
  fprintf('\n');
end

[Shawn Fernandes]

Dear Walter,

I am facing below error during execution

Error using cell/unique (line 85) Input A must be a cell array of strings.

Error in Randomised_Spectral_clustering_gplot (line 163) unique_nodes = unique( vertcat(used_nodes{:}) );

It gets resolved with unique_nodes = unique( cell2table(vertcat(used_nodes{:})) );