Module org.chocosolver

Package org.chocosolver.solver.search.strategy.selectors.variables

Class ActivityBased

java.lang.Object

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

org.chocosolver.solver.search.strategy.selectors.variables.ActivityBased

All Implemented Interfaces:

Comparator<IntVar>, ICause, IMonitorDownBranch, IMonitorRestart, ISearchMonitor, IVariableMonitor<IntVar>

public class ActivityBased
extends AbstractStrategy<IntVar>
implements IMonitorDownBranch, IMonitorRestart, IVariableMonitor<IntVar>, Comparator<IntVar>

Implementation of the search described in: "Activity-Based Search for Black-Box Constraint Propagramming Solver", Laurent Michel and Pascal Van Hentenryck, CPAIOR12.

Since:

07/06/12

Author:

Charles Prud'homme

Constructor Summary

Constructors

Constructor	Description
ActivityBased(Model model, IntVar[] vars, double g, double d, int a, int samplingIterationForced, long seed)
ActivityBased(IntVar[] vars)

Method Summary

Modifier and Type	Method	Description
void	afterDownBranch(boolean left)	Action to perform after going down in the tree search
void	afterRestart()	Actions to execute after restarting the search
void	beforeDownBranch(boolean left)	Action to perform before going down in the tree search
void	beforeRestart()	Actions to execute before restarting the search
int	compare(IntVar o1, IntVar o2)
Decision<IntVar>	computeDecision(IntVar variable)	Computes a decision to be applied to variable var This method should be implemented in order to use search patterns
double	getActivity(IntVar var)
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	onUpdate(IntVar var, IEventType evt)	Operations to execute after updating the domain variable
void	remove()	Remove the current strategy.

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

getVariables, makeIntDecision, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Methods inherited from interface org.chocosolver.solver.ICause

explain, forEachIntVar

Constructor Detail

ActivityBased

public ActivityBased(Model model,
                     IntVar[] vars,
                     double g,
                     double d,
                     int a,
                     int samplingIterationForced,
                     long seed)

ActivityBased

public ActivityBased(IntVar[] vars)

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>

computeDecision

public Decision<IntVar> computeDecision(IntVar variable)

Description copied from class: AbstractStrategy

Computes a decision to be applied to variable var This method should be implemented in order to use search patterns

Overrides:

computeDecision in class AbstractStrategy<IntVar>

Parameters:

variable - a variable

Returns:

a decision to be applied to variable var

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

compare

public int compare(IntVar o1,
                   IntVar o2)

Specified by:

compare in interface Comparator<IntVar>

getActivity

public double getActivity(IntVar var)

onUpdate

public void onUpdate(IntVar var,
                     IEventType evt)

Description copied from interface: IVariableMonitor

Operations to execute after updating the domain variable

Specified by:

onUpdate in interface IVariableMonitor<IntVar>

Parameters:

var - variable concerned

evt - modification event

beforeDownBranch

public void beforeDownBranch(boolean left)

Description copied from interface: IMonitorDownBranch

Action to perform before going down in the tree search

Specified by:

beforeDownBranch in interface IMonitorDownBranch

Parameters:

left - set to true to specify that this is a left branch

afterDownBranch

public void afterDownBranch(boolean left)

Description copied from interface: IMonitorDownBranch

Action to perform after going down in the tree search

Specified by:

afterDownBranch in interface IMonitorDownBranch

Parameters:

left - set to true to specify that this is a left branch

beforeRestart

public void beforeRestart()

Description copied from interface: IMonitorRestart

Actions to execute before restarting the search

Specified by:

beforeRestart in interface IMonitorRestart

afterRestart

public void afterRestart()

Description copied from interface: IMonitorRestart

Actions to execute after restarting the search

Specified by:

afterRestart in interface IMonitorRestart