org.jgrapht.generate

Class ComplementGraphGenerator<V,E>

java.lang.Object

org.jgrapht.generate.ComplementGraphGenerator<V,E>

Type Parameters:

V - vertex type

E - edge type

All Implemented Interfaces:

GraphGenerator<V,E,V>

public class ComplementGraphGenerator<V,E>
extends Object
implements GraphGenerator<V,E,V>

Generator which produces the complement graph of a given input graph. The complement $\overline{G}$ of a graph $G$ consists of the same vertices as $G$, but whose edge set consists of the edges not in $G$.

More formally, let $G = (V, E)$ be a graph and let $K$ consist of all 2-element subsets of $V$. Then $\overline{G} = (V, K \setminus E)$ is the complement of $G$, where $K \setminus E$ is the relative complement of $E$ in $K$. For directed graphs, the complement can be defined in the same way, as a directed graph on the same vertex set, using the set of all 2-element ordered pairs of $V$ in place of the set $K$ in the formula above.

The complement is not defined for multigraphs. If a multigraph is provided as input to this generator, it will be treated as if it is a simple graph.

Author:

Joris Kinable

Constructor Summary

Constructors

Constructor and Description
ComplementGraphGenerator(Graph<V,E> graph) Complement Graph Generator
ComplementGraphGenerator(Graph<V,E> graph, boolean generateSelfLoops) Complement Graph Generator.

Method Summary

Modifier and Type	Method and Description
void	generateGraph(Graph<V,E> target, Map<String,V> resultMap) Generate a graph structure.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.jgrapht.generate.GraphGenerator

generateGraph

Constructor Detail

ComplementGraphGenerator

public ComplementGraphGenerator(Graph<V,E> graph)

Complement Graph Generator

Parameters:

graph - input graph

ComplementGraphGenerator

public ComplementGraphGenerator(Graph<V,E> graph,
                                boolean generateSelfLoops)

Complement Graph Generator. If the target graph allows self-loops the complement of $G$ may be defined by adding a self-loop to every vertex that does not have one in $G$. This behavior can be controlled using the boolean generateSelfLoops.

Parameters:

graph - input graph

generateSelfLoops - indicator whether self loops should be generated. If false, no self-loops are generated, independent of whether the target graph supports self-loops.

Method Detail

generateGraph

public void generateGraph(Graph<V,E> target,
                          Map<String,V> resultMap)

Description copied from interface: GraphGenerator

Generate a graph structure. The topology of the generated graph is dependent on the implementation. For graphs in which not all vertices share the same automorphism equivalence class, the generator may produce a labeling indicating the roles played by generated elements. This is the purpose of the resultMap parameter. For example, a generator for a wheel graph would designate a hub vertex. Role names used as keys in resultMap should be declared as public static final Strings by implementation classes.

Specified by:

generateGraph in interface GraphGenerator<V,E,V>

Parameters:

target - receives the generated edges and vertices; if this is non-empty on entry, the result will be a disconnected graph since generated elements will not be connected to existing elements

resultMap - if non-null, receives implementation-specific mappings from String roles to graph elements (or collections of graph elements)