Module org.chocosolver.solver

Package org.chocosolver.solver.variables

Interface SetVar

All Superinterfaces:

Comparable<Variable>, Identity, Variable

All Known Implementing Classes:

SetVarImpl

public interface SetVar
extends Variable

A Set Variable is defined by a domain which is a set interval [LB,UB], where: LB is the set of integers that must belong to every single solution. UB is the set of integers that may belong to at least one solution.

One must notice that in this context, a VALUE of the variable is a set of integers.

Since:

15 nov. 2012 Major update 2016

Author:

Charles Prud'homme, Jean-Guillaume Fages

Field Summary

Fields inherited from interface org.chocosolver.solver.variables.Variable

BOOL, CSTE, INT, KIND, REAL, SET, TYPE, VAR, VIEW

Method Summary

Modifier and Type	Method	Description
boolean	force(int element, ICause cause)	Adds element to the lower bound, i.e. every solution must include element
IntVar	getCard()	get the constrained cardinality variable of this set.
ISet	getLB()	Get SetVar Lower Bound : the set of integers that must belong to every solution (i.e. a subset of all solutions) To iterate over this set, use the following loop: ISet lbSet = getLB(); for(int i : lbSet){ ... } This object is read-only.
ISet	getUB()	Get SetVar Upper Bound : the set of integers that may belong to a solution (i.e. a superset of all solutions) To iterate over this set, use the following loop: ISet ubSet = getUB(); for(int i : ubSet){ ... } This object is read-only.
default ISet	getValue()	Retrieves the current value of the variable if instantiated, otherwise the lower bound (kernel).
boolean	hasCard()
boolean	instantiateTo(int[] value, ICause cause)	Enforces the set variable to contain exactly the set of integers given in parameter
ISetDeltaMonitor	monitorDelta(ICause propagator)	Allow propagator to monitor element removal/enforcing of this
boolean	remove(int element, ICause cause)	Removes element from the upper bound, i.e. the set variable cannot contain element anymore
void	setCard(IntVar card)	ensure a variable is equal to the cardinality of this set.

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface org.chocosolver.solver.Identity

getId

Methods inherited from interface org.chocosolver.solver.variables.Variable

addMonitor, asBoolVar, asIntVar, asRealVar, asSetVar, clearEvents, contradiction, createDelta, getCause, getDelta, getDindex, getEnvironment, getEvtScheduler, getIndexInPropagator, getMask, getModel, getName, getNbProps, getNbViews, getPIndices, getPropagator, getPropagators, getTypeAndKind, getView, isAConstant, isInstantiated, link, notifyMonitors, notifyPropagators, notifyViews, removeMonitor, setPIndice, storeEvents, subscribeView, swapOnActivate, swapOnPassivate, unlink

Method Detail

getLB

ISet getLB()

Get SetVar Lower Bound : the set of integers that must belong to every solution (i.e. a subset of all solutions) To iterate over this set, use the following loop: ISet lbSet = getLB(); for(int i : lbSet){ ... } This object is read-only. Use variable methods force to update the domain

Returns:

the lower bound of this SetVar.

getUB

ISet getUB()

Get SetVar Upper Bound : the set of integers that may belong to a solution (i.e. a superset of all solutions) To iterate over this set, use the following loop: ISet ubSet = getUB(); for(int i : ubSet){ ... } This object is read-only. Use variable methods remove to update the domain

Returns:

the lower bound of this SetVar.

getCard

IntVar getCard()

get the constrained cardinality variable of this set.

• if no variable already has this role, creates a new variable, store and constraint it.
• if a variable already has this role, return it.

Returns:

a variable constrained to this set cardinality. Successive calls should return the same value

hasCard

boolean hasCard()

Returns:

true if a variable is constrained to this set's cardinality, false otherwise

setCard

void setCard(IntVar card)

ensure a variable is equal to the cardinality of this set.

• If not call has been already performed to this set cardinality, post a constraint on the number of variables
• if this set already has a variable constrained to the cardinality, post an equality

Parameters:

card - a variable of the same model.

force

boolean force(int element,
              ICause cause)
       throws ContradictionException

Adds element to the lower bound, i.e. every solution must include element

Parameters:

element - value to add

cause - cause of value addition

Returns:

true iff element has been added to the lower bound

Throws:

ContradictionException

remove

boolean remove(int element,
               ICause cause)
        throws ContradictionException

Removes element from the upper bound, i.e. the set variable cannot contain element anymore

Parameters:

element - value to remove

cause - cause of value removal

Returns:

true iff element has been removed from the upper bound

Throws:

ContradictionException

instantiateTo

boolean instantiateTo(int[] value,
                      ICause cause)
               throws ContradictionException

Enforces the set variable to contain exactly the set of integers given in parameter

Parameters:

value - a set of integers

cause - cause of instantiation

Returns:

true iff a domain modification occurred

Throws:

ContradictionException

getValue

default ISet getValue()

Retrieves the current value of the variable if instantiated, otherwise the lower bound (kernel).

Returns:

the current value (or kernel if not yet instantiated).

monitorDelta

ISetDeltaMonitor monitorDelta(ICause propagator)

Allow propagator to monitor element removal/enforcing of this

Parameters:

propagator - observer

Returns:

a new SetDeltaMonitor