sample.rb

# Gviz sample:
# Graphviz Example: Undirected Graph Clusters | Graphviz - Graph Visualization Software
# http://www.graphviz.org/content/fdpclust
require "gviz"

Graph(:G, :graph) do
  global layout:'fdp'
  node :e
  subgraph(:clusterA) do
    route :a => :b
    subgraph(:clusterC) do
      route :C => :D
    end
  end
  
  subgraph(:clusterB) do
    route :d => :f
  end

  route :d => :D
  route :e => :clusterB
  route :clusterC => :clusterB
  
  save :sample
end