Module org.jgrapht.core
Package org.jgrapht.generate

Class ComplementGraphGenerator<V,​E>

  • Type Parameters:
    V - vertex type
    E - edge type
    All Implemented Interfaces:
    GraphGenerator<V,​E,​V>
    public class ComplementGraphGenerator<V,​E>
extends java.lang.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 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,
                          java.util.Map<java.lang.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)