Package net.sf.tweety.math.opt.solver

Class BfgsSolver

java.lang.Object

net.sf.tweety.math.opt.Solver

net.sf.tweety.math.opt.solver.BfgsSolver

public class BfgsSolver
extends Solver

This class implements the BFGS algorithm for solving unconstrained optimization problems.

Author:

Matthias Thimm

Field Summary

Fields

Modifier and Type	Field	Description
private org.slf4j.Logger	log	Logger.
private static double	PRECISION
private java.util.Map<Variable,Term>	startingPoint	The starting point for the solver.

Constructor Summary

Constructors

Constructor	Description
BfgsSolver(java.util.Map<Variable,Term> startingPoint)

Method Summary

Modifier and Type	Method	Description
private Matrix	evaluate(Matrix gradient, Matrix currentGuess, java.util.List<Variable> variables)
static boolean	isInstalled()
private double	nextBestStep(Matrix currentGuess, Matrix searchDirection, Matrix gradient, java.util.List<Variable> variables)
java.util.Map<Variable,Term>	solve(ConstraintSatisfactionProblem problem)	Computes a solution to the given constraint satisfaction or optimization problem, i.e.

Methods inherited from class net.sf.tweety.math.opt.Solver

getDefaultGeneralSolver, getDefaultIntegerLinearSolver, getDefaultLinearSolver, hasDefaultGeneralSolver, hasDefaultIntegerLinearSolver, hasDefaultLinearSolver, setDefaultGeneralSolver, setDefaultIntegerLinearSolver, setDefaultLinearSolver

Methods inherited from class java.lang.Object

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

Field Detail

log

private org.slf4j.Logger log

Logger.

PRECISION

private static final double PRECISION

See Also:

Constant Field Values

startingPoint

private java.util.Map<Variable,Term> startingPoint

The starting point for the solver.

Constructor Detail

BfgsSolver

public BfgsSolver(java.util.Map<Variable,Term> startingPoint)

Method Detail

solve

public java.util.Map<Variable,Term> solve(ConstraintSatisfactionProblem problem)
                                         throws GeneralMathException

Description copied from class: Solver

Computes a solution to the given constraint satisfaction or optimization problem, i.e. a mapping from variables of the problem to terms.

Specified by:

solve in class Solver

Parameters:

problem - the actual problem

Returns:

a mapping from variables of the problem to terms.

Throws:

GeneralMathException - if something went wrong.

nextBestStep

private double nextBestStep(Matrix currentGuess,
                            Matrix searchDirection,
                            Matrix gradient,
                            java.util.List<Variable> variables)

evaluate

private Matrix evaluate(Matrix gradient,
                        Matrix currentGuess,
                        java.util.List<Variable> variables)

isInstalled

public static boolean isInstalled()
                           throws java.lang.UnsupportedOperationException

Throws:

java.lang.UnsupportedOperationException