Package org.drip.graph.astar

Class VertexContextEpsilonAdmissibleHeuristic

java.lang.Object

org.drip.graph.astar.VertexContextEpsilonAdmissibleHeuristic

public class VertexContextEpsilonAdmissibleHeuristic
extends java.lang.Object

VertexContextEpsilonAdmissibleHeuristic computes the Reese (1999) Epsilon-Admissible Heuristic in the Alpha A^* Heuristic Function. The References are:

• Dechter, R., and J. Pearl (1985): Generalized Best-first Search Strategies and the Optimality of A^* Journal of the ACM 32 (3) 505-536
• Hart, P. E., N. J. Nilsson, and B. Raphael (1968): A Formal Basis for the Heuristic Determination of the Minimum Cost Paths IEEE Transactions on Systems Sciences and Cybernetics 4 (2) 100-107
• Kagan, E., and I. Ben-Gal (2014): A Group Testing Algorithm with Online Informational Learning IIE Transactions 46 (2) 164-184
• Russell, S. J. and P. Norvig (2018): Artificial Intelligence: A Modern Approach 4^th Edition Pearson
• Wikipedia (2020): A^* Search Algorithm https://en.wikipedia.org/wiki/A*_search_algorithm

• Module = Computational Core Module
• Library = Graph Algorithm Library
• Project = Graph Optimization and Tree Construction Algorithms
• Package = A^* Heuristic Shortest Path Family

Author:

Lakshmi Krishnamurthy

Constructor Summary

Constructors

Constructor	Description
VertexContextEpsilonAdmissibleHeuristic(FHeuristic fHeuristic, VertexContextWeightHeuristic vertexContextWeightHeuristic)	VertexContextEpsilonAdmissibleHeuristic Constructor

Method Summary

Modifier and Type	Method	Description
static VertexContextEpsilonAdmissibleHeuristic	AlphaAStar(VertexFunction gHeuristic, VertexFunction hHeuristic, double smallLambda, double bigLambda)	Construct the Reese (1999) Alpha A* Epsilon-Admissible Heuristic Function
double	evaluate(VertexContext vertexContext)	Compute the Epsilon-Admissible Heuristic for the Specified Vertex Context
FHeuristic	fHeuristic()	Retrieve the F Heuristic
VertexContextWeightHeuristic	vertexContextWeightHeuristic()	Retrieve the Vertex Context Weight Heuristic

Methods inherited from class java.lang.Object

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

Constructor Details

VertexContextEpsilonAdmissibleHeuristic

public VertexContextEpsilonAdmissibleHeuristic(FHeuristic fHeuristic,
VertexContextWeightHeuristic vertexContextWeightHeuristic)
                                        throws java.lang.Exception

VertexContextEpsilonAdmissibleHeuristic Constructor

Parameters:

fHeuristic - The F Heuristic

vertexContextWeightHeuristic - The Vertex Context Weight Heuristic

Throws:

java.lang.Exception - Thrown if the Inputs are Invalid

Method Details

AlphaAStar

public static final VertexContextEpsilonAdmissibleHeuristic AlphaAStar(VertexFunction gHeuristic,
VertexFunction hHeuristic,
double smallLambda,
double bigLambda)

Construct the Reese (1999) Alpha A^* Epsilon-Admissible Heuristic Function

Parameters:

gHeuristic - The G Heuristic

hHeuristic - The H Heuristic

smallLambda - The Small Lambda

bigLambda - The Big Lambda

Returns:

The Reese (1999) Alpha A^* Epsilon-Admissible Heuristic Function

fHeuristic

public FHeuristic fHeuristic()

Retrieve the F Heuristic

Returns:

The F Heuristic

vertexContextWeightHeuristic

public VertexContextWeightHeuristic vertexContextWeightHeuristic()

Retrieve the Vertex Context Weight Heuristic

Returns:

The Vertex Context Weight Heuristic

evaluate

public double evaluate(VertexContext vertexContext)
                throws java.lang.Exception

Compute the Epsilon-Admissible Heuristic for the Specified Vertex Context

Parameters:

vertexContext - The vertex Context

Returns:

The Epsilon-Admissible Heuristic for the Specified Vertex Context

Throws:

java.lang.Exception - Thrown if the Inputs are Invalid