1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
#--
# Copyright (c) 2006 Shawn Patrick Garbett
# Copyright (c) 2002,2004,2005 by Horst Duchene
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice(s),
# this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
# * Neither the name of the Shawn Garbett nor the names of its contributors
# may be used to endorse or promote products derived from this software
# without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#++
require 'puppet/gratr/edge'
require 'puppet/gratr/graph'
require 'set'
module GRATR
# This provides the basic routines needed to implement the Digraph, UndirectedGraph,
# PseudoGraph, DirectedPseudoGraph, MultiGraph and DirectedPseudoGraph class.
module AdjacencyGraph
include Graph
class ArrayWithAdd < Array # :nodoc:
alias add push
end
# Initialization parameters can include an Array of edges to add, Graphs to
# copy (will merge if multiple)
# :parallel_edges denotes that duplicate edges are allowed
# :loops denotes that loops are allowed
def initialize(*params)
@vertex_dict = Hash.new
raise ArgumentError if params.any? do |p|
!(p.kind_of? GRATR::Graph or
p.kind_of? Array or
p == :parallel_edges or
p == :loops)
end
clear_all_labels
# Basic configuration of adjacency
@allow_loops = params.any? {|p| p == :loops}
@parallel_edges = params.any? {|p| p == :parallel_edges}
@edgelist_class = @parallel_edges ? ArrayWithAdd : Set
if @parallel_edges
@edge_number = Hash.new
@next_edge_number = 0
end
# Copy any given graph into this graph
params.select {|p| p.kind_of? GRATR::Graph}.each do |g|
g.edges.each do |e|
add_edge!(e)
edge_label_set(e, edge_label(e)) if edge_label(e)
end
g.vertices.each do |v|
vertex_label_set(v, vertex_label(v)) if vertex_label(v)
end
end
# Add all array edges specified
params.select {|p| p.kind_of? Array}.each do |a|
0.step(a.size-1, 2) {|i| add_edge!(a[i], a[i+1])}
end
end
# Returns true if v is a vertex of this Graph
# An O(1) implementation of vertex?
def vertex?(v) @vertex_dict.has_key?(v); end
# Returns true if [u,v] or u is an Edge
# An O(1) implementation
def edge?(u, v=nil)
u, v = u.source, u.target if u.kind_of? GRATR::Edge
vertex?(u) and @vertex_dict[u].include?(v)
end
# Adds a vertex to the graph with an optional label
def add_vertex!(vertex, label=nil)
@vertex_dict[vertex] ||= @edgelist_class.new
self[vertex] = label if label
self
end
# Adds an edge to the graph
# Can be called in two basic ways, label is optional
# * add_edge!(Edge[source,target], "Label")
# * add_edge!(source,target, "Label")
def add_edge!(u, v=nil, l=nil, n=nil)
n = u.number if u.class.include? EdgeNumber and n.nil?
u, v, l = u.source, u.target, u.label if u.kind_of? GRATR::Edge
return self if not @allow_loops and u == v
n = (@next_edge_number+=1) unless n if @parallel_edges
add_vertex!(u); add_vertex!(v)
@vertex_dict[u].add(v)
(@edge_number[u] ||= @edgelist_class.new).add(n) if @parallel_edges
unless directed?
@vertex_dict[v].add(u)
(@edge_number[v] ||= @edgelist_class.new).add(n) if @parallel_edges
end
self[n ? edge_class[u,v,n] : edge_class[u,v]] = l if l
self
end
# Removes a given vertex from the graph
def remove_vertex!(v)
# FIXME This is broken for multi graphs
@vertex_dict.delete(v)
@vertex_dict.each_value { |adjList| adjList.delete(v) }
@vertex_dict.keys.each do |u|
delete_label(edge_class[u,v])
delete_label(edge_class[v,u])
end
delete_label(v)
self
end
# Removes an edge from the graph, can be called with source and target or with
# and object of GRATR::Edge derivation
def remove_edge!(u, v=nil)
unless u.kind_of? GRATR::Edge
raise ArgumentError if @parallel_edges
u = edge_class[u,v]
end
raise ArgumentError if @parallel_edges and (u.number || 0) == 0
return self unless @vertex_dict[u.source] # It doesn't exist
delete_label(u) # Get rid of label
if @parallel_edges
index = @edge_number[u.source].index(u.number)
raise NoEdgeError unless index
@vertex_dict[u.source].delete_at(index)
@edge_number[u.source].delete_at(index)
else
@vertex_dict[u.source].delete(u.target)
end
self
end
# Returns an array of vertices that the graph has
def vertices() @vertex_dict.keys; end
# Returns an array of edges, most likely of class Edge or UndirectedEdge depending
# upon the type of graph
def edges
@vertex_dict.keys.inject(Set.new) do |a,v|
if @parallel_edges and @edge_number[v]
@vertex_dict[v].zip(@edge_number[v]).each do |w|
s,t,n = v,w[0],w[1]
a.add( edge_class[ s,t,n, edge_label(s,t,n) ] )
end
else
@vertex_dict[v].each do |w|
a.add(edge_class[v,w,edge_label(v,w)])
end
end; a
end.to_a
end
alias graph_adjacent adjacent
def adjacent(x, options={})
unless @vertex_dict.has_key?(x)
raise ArgumentError, "%s is not a vertex" % x
end
options[:direction] ||= :out
if !x.kind_of?(GRATR::Edge) and (options[:direction] == :out || !directed?)
if options[:type] == :edges
@parallel_edges ?
@vertex_dict[x].map {|v| e=edge_class[x,v,@edge_number[x][v]]; e.label = self[e]; e} :
@vertex_dict[x].map {|v| e=edge_class[x,v]; e.label = self[e]; e}
else
@vertex_dict[x].to_a
end
else
graph_adjacent(x,options)
end
end
public
def self.included(cl)
# Shortcut for creating a Graph
#
# Example: GRATR::Digraph[1,2, 2,3, 2,4, 4,5].edges.to_a.to_s =>
# "(1-2)(2-3)(2-4)(4-5)"
#
# Or as a Hash for specifying lables
# GRATR::Digraph[ [:a,:b] => 3, [:b,:c] => 4 ] (Note: Do not use for Multi or Pseudo graphs)
def cl.[] (*a)
result = new
if a.size == 1 and a[0].kind_of? Hash
# Convert to edge class
a[0].each do |k,v|
if result.edge_class.include? GRATR::EdgeNumber
result.add_edge!(result.edge_class[k[0],k[1],nil,v])
else
result.add_edge!(result.edge_class[k[0],k[1],v])
end
end
elsif a[0].kind_of? GRATR::Edge
a.each{|e| result.add_edge!(e); result[e] = e.label}
elsif a.size % 2 == 0
0.step(a.size-1, 2) {|i| result.add_edge!(a[i], a[i+1])}
else
raise ArgumentError
end
result
end
end
end # Adjacency Graph
end # GRATR
|
