Graph::D3 - Create ref/json to show node-edge graph with D3.js

       Shohei Kameda <shoheik@cpan.org>

       Copyright 2013- Shohei Kameda

       Graph::D3 is a moudle to covert Graph object to the format which is used in d3.js(http://d3js.org/).
       This module simply supports node-edge graph in the example.

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.

force_directed_graph
       This outputs the format which is used for Force Directed Graph described below.

       https://gist.github.com/mbostock/4062045,http://bl.ocks.org/mbostock/4062045

       The input graph should be directed grpah.  Node in Graph can have 'group' attribute (Default is all 1) to
       have different node color.  Also Edge in Graph can have 'value' attribe(defalut is all 1).

   hierarchical_edge_bundlinghttp://mbostock.github.io/d3/talk/20111116/bundle.html

       The input graph shoudl be directed graph.  Node in Graph can have 'size' attribute (Default is all 1).

       Graph::D3 - Create ref/json to show node-edge graph with D3.js

perl v5.34.0                                       2022-06-14                                     Graph::D3(3pm)

         use Graph;
         use Graph::D3;
         my $g = new Graph(
             vertices => [qw/1 2 3 4 5/],
             edges => [[qw/1 2/], [qw/2 3/], [qw/3 5/], [qw/4 1/]]
         );
         my $d3 = new Graph::D3(graph => $g);
         my $output = $d3->force_directed_graph(); #output is hash reference
         $output = $d3->hierarchical_edge_bundling(); #output is hash reference

         $d3 = new Graph::D3(graph => $g, type => json);
         my $json = $d3->force_directed_graph(); # output is json format
         $json = $d3->hierarchical_edge_bundling(); # output is json format