org.jacop.constraints

Class SumWeight

java.lang.Object

org.jacop.constraints.DecomposedConstraint

org.jacop.constraints.Constraint

org.jacop.constraints.SumWeight

public class SumWeight
extends Constraint

SumWeight constraint implements the weighted summation over several variables . It provides the weighted sum from all variables on the list. The weights are integers.

Version:

3.1

Author:

Krzysztof Kuchcinski and Radoslaw Szymanek

Field Summary

Fields

Modifier and Type	Field and Description
IntVar[]	list It specifies a list of variables being summed.
IntVar	sum It specifies variable for the overall sum.
int[]	weights It specifies a list of weights associated with the variables being summed.
static String[]	xmlAttributes It specifies the arguments required to be saved by an XML format as well as the constructor being called to recreate an object from an XML format.

Fields inherited from class org.jacop.constraints.Constraint

atomicExecution, consistencyPruningEvents, earlyTerminationOK, id, increaseWeight, numberArgs, numberId, trace

Fields inherited from class org.jacop.constraints.DecomposedConstraint

queueIndex

Constructor Summary

Constructors

Constructor and Description
SumWeight(ArrayList<? extends IntVar> variables, ArrayList<Integer> weights, IntVar sum) It constructs the constraint SumWeight.
SumWeight(IntVar[] list, int[] weights, IntVar sum)

Method Summary

Modifier and Type	Method and Description
ArrayList<Var>	arguments() It returns the variables in a scope of the constraint.
void	consistency(Store store) It is a (most probably incomplete) consistency function which removes the values from variables domains.
int	getConsistencyPruningEvent(Var var) It retrieves the pruning event which causes reevaluation of the constraint.
void	impose(Store store) It imposes the constraint in a given store.
void	increaseWeight() It increases the weight of the variables in the constraint scope.
void	queueVariable(int level, Var var) This is a function called to indicate which variable in a scope of constraint has changed.
void	removeConstraint() It removes the constraint by removing this constraint from all variables.
void	removeLevelLate(int level) This function is called in case of the backtrack.
boolean	satisfied() It checks if the constraint is satisfied.
String	toString() It produces a string representation of a constraint state.

Methods inherited from class org.jacop.constraints.Constraint

cleanAfterFailure, decompose, getGuideConstraint, getGuideValue, getGuideVariable, id, impose, imposeDecomposition, numberArgs, removeLevel, requiresMonotonicity, setConsistencyPruningEvent, supplyGuideFeedback

Methods inherited from class org.jacop.constraints.DecomposedConstraint

auxiliaryVariables, derivative, imposeDecomposition

Methods inherited from class java.lang.Object

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

Field Detail

list

public IntVar[] list

It specifies a list of variables being summed.

weights

public int[] weights

It specifies a list of weights associated with the variables being summed.

sum

public IntVar sum

It specifies variable for the overall sum.

xmlAttributes

public static String[] xmlAttributes

It specifies the arguments required to be saved by an XML format as well as the constructor being called to recreate an object from an XML format.

Constructor Detail

SumWeight

public SumWeight(IntVar[] list,
                 int[] weights,
                 IntVar sum)

Parameters:

list -

weights -

sum -

SumWeight

public SumWeight(ArrayList<? extends IntVar> variables,
                 ArrayList<Integer> weights,
                 IntVar sum)

It constructs the constraint SumWeight.

Parameters:

variables - variables which are being multiplied by weights.

weights - weight for each variable.

sum - variable containing the sum of weighted variables.

Method Detail

arguments

public ArrayList<Var> arguments()

Description copied from class: Constraint

It returns the variables in a scope of the constraint.

Specified by:

arguments in class Constraint

Returns:

variables in a scope of the constraint.

removeLevelLate

public void removeLevelLate(int level)

Description copied from class: Constraint

This function is called in case of the backtrack. It is called after all timestamps, variables, mutablevariables have reverted to their values *after* removing the level.

Overrides:

removeLevelLate in class Constraint

Parameters:

level - the level which is being removed.

consistency

public void consistency(Store store)

Description copied from class: Constraint

It is a (most probably incomplete) consistency function which removes the values from variables domains. Only values which do not have any support in a solution space are removed.

Specified by:

consistency in class Constraint

Parameters:

store - constraint store within which the constraint consistency is being checked.

getConsistencyPruningEvent

public int getConsistencyPruningEvent(Var var)

Description copied from class: Constraint

It retrieves the pruning event which causes reevaluation of the constraint.

Specified by:

getConsistencyPruningEvent in class Constraint

Parameters:

var - variable for which pruning event is retrieved

Returns:

it returns the int code of the pruning event (GROUND, BOUND, ANY, NONE)

impose

public void impose(Store store)

Description copied from class: Constraint

It imposes the constraint in a given store.

Specified by:

impose in class Constraint

Parameters:

store - the constraint store to which the constraint is imposed to.

queueVariable

public void queueVariable(int level,
                          Var var)

Description copied from class: Constraint

This is a function called to indicate which variable in a scope of constraint has changed. It also indicates a store level at which the change has occurred.

Overrides:

queueVariable in class Constraint

Parameters:

level - the level of the store at which the change has occurred.

var - variable which has changed.

removeConstraint

public void removeConstraint()

Description copied from class: Constraint

It removes the constraint by removing this constraint from all variables.

Specified by:

removeConstraint in class Constraint

satisfied

public boolean satisfied()

Description copied from class: Constraint

It checks if the constraint is satisfied. If this function is incorrectly implemented a constraint may not be satisfied in a solution.

Specified by:

satisfied in class Constraint

Returns:

true if the constraint is for certain satisfied, false otherwise.

toString

public String toString()

Description copied from class: Constraint

It produces a string representation of a constraint state.

Specified by:

toString in class Constraint

increaseWeight

public void increaseWeight()

Description copied from class: Constraint

It increases the weight of the variables in the constraint scope.

Specified by:

increaseWeight in class Constraint