Contents

require 'ostruct'

# A simple graph library

module GraphNjae
  # A vertex in a graph. The edge can have arbitrary attributes,treated as 
  # method names.
  class Vertex < OpenStruct
    def initialize
      super
      self.edges = []
      self
    end
    
    # Connect this vertex to another, creating an Edge to do so, and returning
    # the Edge
    def connect(other)
      e = Edge.new
      e << self << other
      self.edges << e
      other.edges << e unless self === other
      e
    end
    
    # Connect this vertex to another, creating an Edge to do so, and returning
    # this Vertex
    def <<(other)
      connect(other)
      self
    end
    
    # Return the set of neighbouring vertices
    def neighbours
      vertices = self.edges.map {|e| e.vertices}.flatten
      vertices_to_me = vertices.select {|v| v == self}
      other_vertices = vertices.select {|v| v != self}
      (vertices_to_me[1..-1] || []) + other_vertices
    end
    
  end
end

Version data entries

3 entries across 3 versions & 1 rubygems

Version	Path
graph.njae-0.2.2	lib/graph.njae/vertex.rb
graph.njae-0.2.1	lib/graph.njae/vertex.rb
graph.njae-0.2.0	lib/graph.njae/vertex.rb