org.chocosolver.solver.constraints.nary.cumulative

Class PropFullCumulative

java.lang.Object

org.chocosolver.solver.constraints.Propagator<IntVar>

org.chocosolver.solver.constraints.nary.cumulative.PropFullCumulative

All Implemented Interfaces:

Serializable, Comparable<Propagator>, ICause, Identity

Direct Known Subclasses:

PropGraphCumulative

public class PropFullCumulative
extends Propagator<IntVar>

Cumulative propagator Performs energy checking and mandatory part based filtering BEWARE : not idempotent, use two propagators to get the fix point

Since:

31/01/13

Author:

Jean-Guillaume Fages

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Cumulative.Filter[]	_filters
protected ISet	allTasks
protected IntVar	capa
protected IntVar[]	d
protected IntVar[]	e
protected boolean	fast
protected CumulFilter[]	filters
protected IntVar[]	h
protected IStateInt	lastCapaMax
protected int	n
protected IntVar[]	s

Fields inherited from class org.chocosolver.solver.constraints.Propagator

ACTIVE, constraint, NEW, PASSIVE, priority, reactToFineEvt, REIFIED, solver, vars

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PropFullCumulative(IntVar[] s, IntVar[] d, IntVar[] e, IntVar[] h, IntVar capa, boolean reactToFineEvt, boolean fast, Cumulative.Filter... filters) protected constructor, should not be called by a user
	PropFullCumulative(IntVar[] s, IntVar[] d, IntVar[] e, IntVar[] h, IntVar capa, boolean fast, Cumulative.Filter... filters) Classical cumulative propagator

Method Summary

Modifier and Type	Method and Description
void	filter(ISet tasks)
int	getPropagationConditions(int idx) Returns the specific mask indicating the variable events on which this Propagator object can react.
ESat	isEntailed() Check wether this is entailed according to the current state of its internal structure.
protected void	linkVariables() Creates links between this propagator and its variables.
void	propagate(int evtmask) Call the main filtering algorithm to apply to the Domain of the Variable objects.
protected void	propIni()
String	toString()
protected void	updateMaxCapa()

Methods inherited from class org.chocosolver.solver.constraints.Propagator

addVariable, arity, compareTo, contradiction, decNbPendingEvt, defineIn, dynPriority, fails, flushPendingEvt, forcePropagate, getConstraint, getId, getNbPendingEvt, getNbVars, getPriority, getSolver, getVar, getVars, getVIndices, hashCode, incNbPendingEvt, isActive, isCompletelyInstantiated, isPassive, isReifiedAndSilent, isStateLess, propagate, reactToFineEvent, setActive, setPassive, setReifiedSilent, setReifiedTrue, setVIndices, why

Methods inherited from class java.lang.Object

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

Field Detail

n

protected final int n

s

protected final IntVar[] s

d

protected final IntVar[] d

e

protected final IntVar[] e

h

protected final IntVar[] h

capa

protected final IntVar capa

filters

protected CumulFilter[] filters

allTasks

protected ISet allTasks

fast

protected final boolean fast

lastCapaMax

protected final IStateInt lastCapaMax

_filters

protected final Cumulative.Filter[] _filters

Constructor Detail

PropFullCumulative

protected PropFullCumulative(IntVar[] s,
                             IntVar[] d,
                             IntVar[] e,
                             IntVar[] h,
                             IntVar capa,
                             boolean reactToFineEvt,
                             boolean fast,
                             Cumulative.Filter... filters)

protected constructor, should not be called by a user

PropFullCumulative

public PropFullCumulative(IntVar[] s,
                          IntVar[] d,
                          IntVar[] e,
                          IntVar[] h,
                          IntVar capa,
                          boolean fast,
                          Cumulative.Filter... filters)

Classical cumulative propagator

Parameters:

s - start variables

d - duration variables

e - end variables

h - height variables

capa - capacity variable

fast - optimization parameter: reduces the amount of filtering calls when set to true (only reacts to instantiation events)

filters - filtering algorithm to use

Method Detail

linkVariables

protected void linkVariables()

Description copied from class: Propagator

Creates links between this propagator and its variables. The propagator will then be referenced in each of its variables.

Overrides:

linkVariables in class Propagator<IntVar>

getPropagationConditions

public int getPropagationConditions(int idx)

Description copied from class: Propagator

Returns the specific mask indicating the variable events on which this Propagator object can react.
A mask is a bitwise OR operations over IEventType this can react on. For example, consider a propagator that can deduce filtering based on the lower bound of the integer variable X. Then, for this variable, the mask should be equal to :

     int mask = IntEventType.INCLOW.getMask() | IntEventType.INSTANTIATE.getMask();
 

or, in a more convenient way:

     int mask = IntEvtType.combine(IntEventType.INCLOW,IntEventType.INSTANTIATE);
 

That indicates the following behavior:

1. if X is instantiated, this propagator will be executed,
2. if the lower bound of X is modified, this propagator will be executed,
3. if the lower bound of X is removed, the event is promoted from REMOVE to INCLOW and this propagator will NOT be executed,
4. otherwise, this propagator will NOT be executed

Some combinations are valid. For example, a propagator which reacts on REMOVE and INSTANTIATE should also declare INCLOW and DECUPP as conditions. Indeed INCLOW (resp. DECUPP), for efficiency purpose, removing the lower bound (resp. upper bound) of an integer variable will automatically be promoted into INCLOW (resp. DECUPP). So, ignoring INCLOW and/or DECUPP in that case may result in a lack of filtering. The same goes with events of other variable types, but most of the time, there are only few combinations. Reacts to any kind of event by default. Alternatively, this method can return IntEventType.VOID which states that this propagator should not be aware of modifications applied to the variable in position vIdx.

Overrides:

getPropagationConditions in class Propagator<IntVar>

Parameters:

idx - index of the variable within the propagator

Returns:

an int composed of REMOVE and/or INSTANTIATE and/or DECUPP and/or INCLOW

propagate

public void propagate(int evtmask)
               throws ContradictionException

Description copied from class: Propagator

Call the main filtering algorithm to apply to the Domain of the Variable objects. It considers the current state of this objects to remove some values from domains and/or instantiate some variables. Calling this method is done from 2 (and only 2) steps:
- at the initial propagation step,
- when involved in a reified constraint.
It should initialized the internal data structure and apply filtering algorithm from scratch.

Specified by:

propagate in class Propagator<IntVar>

Parameters:

evtmask - type of propagation event this must consider.

Throws:

ContradictionException - when a contradiction occurs, like domain wipe out or other incoherencies.

propIni

protected void propIni()
                throws ContradictionException

Throws:

ContradictionException

updateMaxCapa

protected void updateMaxCapa()
                      throws ContradictionException

Throws:

ContradictionException

filter

public void filter(ISet tasks)
            throws ContradictionException

Throws:

ContradictionException

isEntailed

public ESat isEntailed()

Description copied from class: Propagator

Check wether this is entailed according to the current state of its internal structure. At least, should check the satisfaction of this (when all is instantiated).

Specified by:

isEntailed in class Propagator<IntVar>

Returns:

ESat.TRUE if entailed, ESat.FALSE if not entailed, ESat.UNDEFINED if unknown

toString

public String toString()

Overrides:

toString in class Propagator<IntVar>