Module org.chocosolver

Package org.chocosolver.solver.objective

Class ObjectiveStrategy

java.lang.Object

org.chocosolver.solver.search.strategy.strategy.AbstractStrategy<IntVar>

org.chocosolver.solver.objective.ObjectiveStrategy

public class ObjectiveStrategy
extends AbstractStrategy<IntVar>

Class that defines a branching strategy over the objective variable

Since:

Oct. 2012

Author:

Jean-Guillaume Fages

Field Summary

Fields inherited from class org.chocosolver.solver.search.strategy.strategy.AbstractStrategy

vars

Constructor Summary

Constructors

Constructor	Description
ObjectiveStrategy(IntVar objective, int[] coefs, OptimizationPolicy policy)	Defines a parametrized dichotomic branching over the objective variable BEWARE: only activated after a first solution
ObjectiveStrategy(IntVar objective, OptimizationPolicy policy)	Defines a branching strategy over the objective variable BEWARE: only activated after a first solution

Method Summary

Modifier and Type	Method	Description
Decision<IntVar>	getDecision()	Provides access to the current decision in the strategy.
boolean	init()	Prepare this to be used in a search loop The initialization can detect inconsistency, in that case, it returns false
void	remove()	Remove the current strategy.

Methods inherited from class org.chocosolver.solver.search.strategy.strategy.AbstractStrategy

computeDecision, getVariables, makeIntDecision, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectiveStrategy

public ObjectiveStrategy(IntVar objective,
                         OptimizationPolicy policy)

Defines a branching strategy over the objective variable BEWARE: only activated after a first solution

Parameters:

objective - variable

policy - BOTTOM_UP, TOP_TOWN or DICHOTOMIC

ObjectiveStrategy

public ObjectiveStrategy(IntVar objective,
                         int[] coefs,
                         OptimizationPolicy policy)

Defines a parametrized dichotomic branching over the objective variable BEWARE: only activated after a first solution

Parameters:

objective - variable

coefs - [a,b] defines how to split the domain of the objective variable [1,1] will halve its domain [1,2] will take a value closer to the upper bound than the lower bound

policy - should be DICHOTOMIC

Method Detail

init

public boolean init()

Description copied from class: AbstractStrategy

Prepare this to be used in a search loop The initialization can detect inconsistency, in that case, it returns false

Overrides:

init in class AbstractStrategy<IntVar>

remove

public void remove()

Description copied from class: AbstractStrategy

Remove the current strategy. This implies unplugging variable or search monitors.

Overrides:

remove in class AbstractStrategy<IntVar>

getDecision

public Decision<IntVar> getDecision()

Description copied from class: AbstractStrategy

Provides access to the current decision in the strategy. If there are no more decision to provide, it returns null.

Specified by:

getDecision in class AbstractStrategy<IntVar>

Returns:

the current decision