edu.stanford.math.plex4.graph.random

Class ManifoldGraph

java.lang.Object

edu.stanford.math.plex4.graph.random.GraphInstanceGenerator

edu.stanford.math.plex4.graph.random.ManifoldGraph

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

KNearestNeighborsGraph, SphereGraph, TorusGraph

public abstract class ManifoldGraph
extends GraphInstanceGenerator

This class is used to create a k-nearest neighbors graph on a manifold. It is abstract, and subclasses are required to implement the metric on the manifold.

Author:

Andrew Tausz

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class edu.stanford.math.plex4.graph.random.GraphInstanceGenerator

GraphInstanceGenerator.ImplementationType

Field Summary

Fields

Modifier and Type	Field and Description
protected double[][]	points

Fields inherited from class edu.stanford.math.plex4.graph.random.GraphInstanceGenerator

graphImplementation, implementationType

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ManifoldGraph(int size, int dimension, int k) Constructor for the ManifoldGraph class.

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract double	distance(double[] x, double[] y) This function must implement the distance function on the manifold.
AbstractUndirectedGraph	generate()
protected abstract void	generatePoints() This function must generate the set of random points on the manifold.
protected void	generateUniformPoints() This function generates points on the d-dimensional cube [0, 1]^d.
protected int[]	getNearestNeighbors(int index) This function gets the indices of the k nearest neighbors to the point at the specified index.

Methods inherited from class edu.stanford.math.plex4.graph.random.GraphInstanceGenerator

initializeGraph, setImplementationType

Methods inherited from class java.lang.Object

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

Field Detail

points

protected double[][] points

Constructor Detail

ManifoldGraph

protected ManifoldGraph(int size,
             int dimension,
             int k)

Constructor for the ManifoldGraph class.

Parameters:

size - the number of points in the graph

dimension - the dimension of the manifold

k - the number of points to connect to

Method Detail

generate

public AbstractUndirectedGraph generate()

Specified by:

generate in class GraphInstanceGenerator

generateUniformPoints

protected void generateUniformPoints()

This function generates points on the d-dimensional cube [0, 1]^d. It is intended for manifolds represented by squares (or cubes) with their edges identified some way.

generatePoints

protected abstract void generatePoints()

This function must generate the set of random points on the manifold.

distance

protected abstract double distance(double[] x,
              double[] y)

This function must implement the distance function on the manifold.

Parameters:

x - the first point

y - the second point

Returns:

the distance between x and y in the manifold

getNearestNeighbors

protected int[] getNearestNeighbors(int index)

This function gets the indices of the k nearest neighbors to the point at the specified index.

Parameters:

index - the index of the point

Returns:

the indices of the k nearest neighbors