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

Class RandomRegularGraphGenerator<V,​E>

java.lang.Object
org.jgrapht.generate.RandomRegularGraphGenerator<V,​E>
Type Parameters:
V - graph node type
E - graph edge type
All Implemented Interfaces:
GraphGenerator<V,​E,​V>
public class RandomRegularGraphGenerator<V,​E>
extends java.lang.Object
implements GraphGenerator<V,​E,​V>
Generate a random $d$-regular undirected graph with $n$ vertices. A regular graph is a graph where each vertex has the same degree, i.e. the same number of neighbors.

The algorithm for the simple case, proposed in [SW99] and extending the one for the non-simple case [W99], runs in expected $\mathcal{O}(nd^2)$ time. It has been proved in [KV03] to sample from the space of random d-regular graphs in a way which is asymptotically uniform at random when $d = \mathcal{O}(n^{1/3 - \epsilon})$.

[KV03] Kim, Jeong Han, and Van H. Vu. "Generating random regular graphs." Proceedings of the thirty-fifth annual ACM symposium on Theory of computing. ACM, 2003. [SW99] Steger, Angelika, and Nicholas C. Wormald. "Generating random regular graphs quickly." Combinatorics, Probability and Computing 8.4 (1999): 377-396. [W99] Wormald, Nicholas C. "Models of random regular graphs." London Mathematical Society Lecture Note Series (1999): 239-298.

Author:
Emilio Cruciani

  • Constructor Summary

    Constructors 
    Constructor Description
    RandomRegularGraphGenerator​(int n, int d)
    Construct a new RandomRegularGraphGenerator.
    RandomRegularGraphGenerator​(int n, int d, long seed)
    Construct a new RandomRegularGraphGenerator.
    RandomRegularGraphGenerator​(int n, int d, java.util.Random rng)
    Construct a new RandomRegularGraphGenerator.

  • Method Summary

    Modifier and Type Method Description
    void generateGraph​(Graph<V,​E> target, java.util.Map<java.lang.String,​V> resultMap)
    Generate a random regular graph.

    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 Details

    • RandomRegularGraphGenerator

      public RandomRegularGraphGenerator​(int n, int d)
      Construct a new RandomRegularGraphGenerator.
      Parameters:
      n - number of nodes
      d - degree of nodes
      Throws:
      java.lang.IllegalArgumentException - if number of nodes is negative
      java.lang.IllegalArgumentException - if degree is negative
      java.lang.IllegalArgumentException - if degree is greater than number of nodes
      java.lang.IllegalArgumentException - if the value "n * d" is odd

    • RandomRegularGraphGenerator

      public RandomRegularGraphGenerator​(int n, int d, long seed)
      Construct a new RandomRegularGraphGenerator.
      Parameters:
      n - number of nodes
      d - degree of nodes
      seed - seed for the random number generator
      Throws:
      java.lang.IllegalArgumentException - if number of nodes is negative
      java.lang.IllegalArgumentException - if degree is negative
      java.lang.IllegalArgumentException - if degree is greater than number of nodes
      java.lang.IllegalArgumentException - if the value "n * d" is odd

    • RandomRegularGraphGenerator

      public RandomRegularGraphGenerator​(int n, int d, java.util.Random rng)
      Construct a new RandomRegularGraphGenerator.
      Parameters:
      n - number of nodes
      d - degree of nodes
      rng - the random number generator to use
      Throws:
      java.lang.IllegalArgumentException - if number of nodes is negative
      java.lang.IllegalArgumentException - if degree is negative
      java.lang.IllegalArgumentException - if degree is greater than number of nodes
      java.lang.IllegalArgumentException - if the value "n * d" is odd

  • Method Details

    • generateGraph

      public void generateGraph​(Graph<V,​E> target, java.util.Map<java.lang.String,​V> resultMap)
      Generate a random regular graph.
      Specified by:
      generateGraph in interface GraphGenerator<V,​E,​V>
      Parameters:
      target - the target graph
      resultMap - the result map
      Throws:
      java.lang.IllegalArgumentException - if target is not an undirected graph
      java.lang.IllegalArgumentException - if "n == d" and the graph is simple