class RGL::DOT::Graph

A graph representation. Whether or not it is rendered as directed or undirected depends on which of the programs dot or neato is used to process and render the graph.

Public Class Methods

new(params = {}, option_list = GRAPH_OPTS) click to toggle source

Creates a new Graph with the params Hash providing settings for all graph options. The option_list parameter restricts those options to the list of valid names it contains. The exception to this is the elements option which, if specified, must be an Enumerable containing a list of nodes, edges, and/or subgraphs.

Calls superclass method
# File lib/rgl/rdot.rb, line 309
def initialize(params = {}, option_list = GRAPH_OPTS)
  super(params, option_list)
  @elements   = params['elements'] ? params['elements'] : []
  @dot_string = 'graph'
end

Public Instance Methods

graph << element → graph click to toggle source

Adds a new node, edge, or subgraph to this graph.

# File lib/rgl/rdot.rb, line 331
def << (element)
  @elements << element
  self
end
Also aliased as: push
each_element {|element| block} → graph click to toggle source

Calls block once for each node, edge, or subgraph contained by this graph, passing the node, edge, or subgraph to the block.

# File lib/rgl/rdot.rb, line 321
def each_element(&block)
  @elements.each(&block)
  self
end
pop → element click to toggle source

Removes the most recently added node, edge, or subgraph from this graph and returns it.

# File lib/rgl/rdot.rb, line 344
def pop
  @elements.pop
end
push(element)
Alias for: <<
to_s(leader = '', indent = ' ') click to toggle source

Returns a string representation of this graph which is consumable by the graphviz tools dot and neato. The leader parameter is used to indent every line of the returned string, and the indent parameter is used to additionally indent nested items.

# File lib/rgl/rdot.rb, line 353
def to_s(leader = '', indent = '    ')
  hdr = leader + @dot_string + (@name.nil? ? '' : ' ' + quote_ID(@name)) + " {\n"

  options = @options.to_a.collect do |name, val|
    unless val.nil?
      if name == 'label'
        leader + indent + "#{quote_ID(name)} = #{quote_label(val)}"
      else
        leader + indent + "#{quote_ID(name)} = #{quote_ID(val)}"
      end
    end
  end.compact.join("\n")

  elements = @elements.collect do |element|
    element.to_s(leader + indent, indent)
  end.join("\n\n")

  hdr + (options.empty? ? '' : options + "\n\n") +
      (elements.empty? ? '' : elements + "\n") + leader + "}"
end