org.sat4j.minisat.orders

Class RandomLiteralSelectionStrategy

java.lang.Object

org.sat4j.minisat.orders.RandomLiteralSelectionStrategy

All Implemented Interfaces:

Serializable, IPhaseSelectionStrategy

public final class RandomLiteralSelectionStrategy
extends Object
implements IPhaseSelectionStrategy

The variable selection strategy randomly picks one phase, either positive or negative.

Author:

leberre

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static Random	RAND

Constructor Summary

Constructors

Constructor and Description
RandomLiteralSelectionStrategy()

Method Summary

Methods

Modifier and Type	Method and Description
void	assignLiteral(int p) indicate that a literal has been satisfied.
void	init(int nlength) that method has the responsibility to initialize all arrays in the heuristics.
void	init(int var, int p) initialize the phase of a given variable to the given value.
int	select(int var) selects the phase of the variable according to a phase selection strategy.
String	toString()
void	updateVar(int p) To be called when the activity of a literal changed.
void	updateVarAtDecisionLevel(int q) Allow to perform a specific action when a literal of the current decision level is updated.

Methods inherited from class java.lang.Object

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

Field Detail

RAND

public static final Random RAND

Since:

2.2

Constructor Detail

RandomLiteralSelectionStrategy

public RandomLiteralSelectionStrategy()

Method Detail

assignLiteral

public void assignLiteral(int p)

Description copied from interface: IPhaseSelectionStrategy

indicate that a literal has been satisfied.

Specified by:

assignLiteral in interface IPhaseSelectionStrategy

init

public void init(int nlength)

Description copied from interface: IPhaseSelectionStrategy

that method has the responsibility to initialize all arrays in the heuristics.

Specified by:

init in interface IPhaseSelectionStrategy

Parameters:

nlength - the number of variables managed by the heuristics.

init

public void init(int var,
        int p)

Description copied from interface: IPhaseSelectionStrategy

initialize the phase of a given variable to the given value. That method is suppose to be called AFTER init(int).

Specified by:

init in interface IPhaseSelectionStrategy

Parameters:

var - a variable

p - it's initial phase

select

public int select(int var)

Description copied from interface: IPhaseSelectionStrategy

selects the phase of the variable according to a phase selection strategy.

Specified by:

select in interface IPhaseSelectionStrategy

Parameters:

var - a variable chosen by the heuristics

Returns:

either var or not var, depending of the selection strategy.

updateVar

public void updateVar(int p)

Description copied from interface: IPhaseSelectionStrategy

To be called when the activity of a literal changed.

Specified by:

updateVar in interface IPhaseSelectionStrategy

Parameters:

p - a literal. The associated variable will be updated.

updateVarAtDecisionLevel

public void updateVarAtDecisionLevel(int q)

Description copied from interface: IPhaseSelectionStrategy

Allow to perform a specific action when a literal of the current decision level is updated. That method is called after IPhaseSelectionStrategy.updateVar(int).

Specified by:

updateVarAtDecisionLevel in interface IPhaseSelectionStrategy

Parameters:

q - a literal

toString

public String toString()

Overrides:

toString in class Object