org.jacop.set.constraints

Class SumWeightedSet

java.lang.Object

org.jacop.constraints.DecomposedConstraint

org.jacop.constraints.Constraint

org.jacop.set.constraints.SumWeightedSet

public class SumWeightedSet
extends Constraint

It computes a weighted sum of the elements in the domain of the given set variable. The sum must be equal to the specified sum variable.

Version:

4.2

Author:

Radoslaw Szymanek and Krzysztof Kuchcinski

Field Summary

Fields

Modifier and Type	Field and Description
SetVar	a A set variable a whose elements contribute with their weight to the sum.
int[]	elements It specifies the list of allowed elements and helps to connect the weight to the element.
IntVar	totalWeight Integer variable containing the total weight of all elements within a set variable a.
int[]	weights It specifies a weight for every element of the allowed element in the domain of set variable a.
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
SumWeightedSet(SetVar a, int[] elements, int[] weights, IntVar totalWeight) It constructs a weighted set sum constraint.
SumWeightedSet(SetVar a, int[] weights, IntVar totalWeight) It constructs a weighted set sum constraint.
SumWeightedSet(SetVar a, IntVar totalWeight) It constructs a weighted set sum constraint.

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.
String	id() It gives the id string of a 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	removeConstraint() It removes the constraint by removing this constraint from all variables.
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, impose, imposeDecomposition, numberArgs, queueVariable, removeLevel, removeLevelLate, 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

a

public SetVar a

A set variable a whose elements contribute with their weight to the sum.

elements

public int[] elements

It specifies the list of allowed elements and helps to connect the weight to the element.

weights

public int[] weights

It specifies a weight for every element of the allowed element in the domain of set variable a.

totalWeight

public IntVar totalWeight

Integer variable containing the total weight of all elements within a set variable a.

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

SumWeightedSet

public SumWeightedSet(SetVar a,
                      int[] elements,
                      int[] weights,
                      IntVar totalWeight)

It constructs a weighted set sum constraint.

Parameters:

a - a set variable for which the weighted sum of its element is computed.

elements - it specifies the elements which are allowed and for which the weight is specified.

weights - the weight for each element present in a.lub().

totalWeight - an integer variable equal to the total weight of the elements in set variable a.

SumWeightedSet

public SumWeightedSet(SetVar a,
                      IntVar totalWeight)

It constructs a weighted set sum constraint. This constructor assumes that every element within a set variable has a weight equal to its value.

Parameters:

a - set variable being used in weighted set constraint.

totalWeight - integer variable containing information about total weight of the elements in set variable a.

SumWeightedSet

public SumWeightedSet(SetVar a,
                      int[] weights,
                      IntVar totalWeight)

It constructs a weighted set sum constraint. This constructor assumes that every element within a set variable has a weight equal to its value.

Parameters:

a - set variable being used in weighted set constraint.

weights - it specifies a weight for each possible element of a set variable.

totalWeight - integer variable containing information about total weight of the elements in set variable a.

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.

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)

id

public String id()

Description copied from class: Constraint

It gives the id string of a constraint.

Overrides:

id in class Constraint

Returns:

string id of the constraint.

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.

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