class RGL::Edge::DirectedEdge

Simply a directed pair (source -> target). Most library functions try do omit to instantiate edges. They instead use two vertex parameters for representing edges (see each_edge). If a client wants to store edges explicitly DirectedEdge or UnDirectedEdge instances are returned (i.e. Graph#edges).

Attributes

source[RW]
target[RW]

Public Class Methods

[](*a) click to toggle source

Can be used to create an edge from a two element array.

   # File lib/rgl/base.rb
36 def self.[](*a)
37   new(a[0], a[1])
38 end
new(a, b) click to toggle source

Create a new DirectedEdge with source a and target b.

   # File lib/rgl/base.rb
42 def initialize(a, b)
43   @source, @target = a, b
44 end

Public Instance Methods

<=>(e) click to toggle source

Sort support is dispatched to the <=> method of Array

   # File lib/rgl/base.rb
89 def <=> e
90   self.to_a <=> e.to_a
91 end
==(edge)
Alias for: eql?
[](index) click to toggle source

Edges can be indexed. edge == edge.source, edge == edge.target for all n>0. Edges can thus be used as a two element array.

   # File lib/rgl/base.rb
68 def [](index)
69   index.zero? ? source : target
70 end
eql?(edge) click to toggle source

Two directed edges (u,v) and (x,y) are equal iff u == x and v == y. eql? is needed when edges are inserted into a Set. eql? is aliased to ==.

   # File lib/rgl/base.rb
49 def eql?(edge)
50   (source == edge.source) && (target == edge.target)
51 end
Also aliased as: ==
hash() click to toggle source
   # File lib/rgl/base.rb
55 def hash
56   source.hash ^ target.hash
57 end
inspect()

Since Ruby 2.0 inspect no longer calls to_s. So we alias it to to_s (fixes #22)

Alias for: to_s
reverse() click to toggle source

Returns (v,u) if self == (u,v).

   # File lib/rgl/base.rb
61 def reverse
62   self.class.new(target, source)
63 end
to_a() click to toggle source

Returns the array [source,target].

   # File lib/rgl/base.rb
83 def to_a
84   [source, target]
85 end
to_s() click to toggle source

DirectedEdge.to_s == “(1-2)”

   # File lib/rgl/base.rb
74 def to_s
75   "(#{source}-#{target})"
76 end
Also aliased as: inspect