public class PropItemToLoad extends Propagator<IntVar>
ACTIVE, constraint, DEFAULT_EXPL, model, operations, OUTPUT_DEFAULT_EXPL, priority, reactToFineEvt, state, vars
Constructor and Description |
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PropItemToLoad(IntVar[] binOfItem,
int[] itemSize,
IntVar[] binLoad,
int offset)
Incremental propagator for a Bin Packing constraint
Propagates item/bin allocations to bin loads
Should be used together with PropLoadToItem
|
Modifier and Type | Method and Description |
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int |
getPropagationConditions(int vIdx)
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. |
ESat |
isEntailed()
Check wether
this is entailed according to the current state of its internal structure. |
void |
propagate(int evtmask)
Call the main filtering algorithm to apply to the
Domain of the Variable objects. |
void |
propagate(int item,
int evtmask)
Incremental filtering algorithm defined within the
Propagator , called whenever the variable
of index idxVarInProp has changed. |
addVariable, arity, compareTo, defaultExplain, doFinePropagation, doFlush, doSchedule, doScheduleEvent, dynPriority, equals, explain, fails, forcePropagate, forcePropagationOnBacktrack, forEachIntVar, getConstraint, getId, getModel, getNbVars, getPosition, getPriority, getVar, getVars, getVIndice, getVIndices, hashCode, isActive, isCompletelyInstantiated, isPassive, isReified, isReifiedAndSilent, isScheduled, isStateLess, linkVariables, reactToFineEvent, reifiedWith, setActive, setActive0, setPassive, setPosition, setReifiedSilent, setReifiedTrue, setVIndices, toString, unlinkVariables, unschedule
public PropItemToLoad(IntVar[] binOfItem, int[] itemSize, IntVar[] binLoad, int offset)
binOfItem
- bin of every item (possibly with offset)itemSize
- size of every itembinLoad
- total load of every binoffset
- index offset: binOfItem[i] = k means item i is in bin k-offsetpublic int getPropagationConditions(int vIdx)
Propagator
Propagator
object can react.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:
IntEventType.VOID
which states
that this propagator should not be aware of modifications applied to the variable in position vIdx.getPropagationConditions
in class Propagator<IntVar>
vIdx
- index of the variable within the propagatorREMOVE
and/or INSTANTIATE
and/or DECUPP
and/or INCLOW
public void propagate(int evtmask) throws ContradictionException
Propagator
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:
propagate
in class Propagator<IntVar>
evtmask
- type of propagation event this
must consider.ContradictionException
- when a contradiction occurs, like domain wipe out or other incoherencies.public void propagate(int item, int evtmask) throws ContradictionException
Propagator
Propagator
, called whenever the variable
of index idxVarInProp has changed. This method calls a CUSTOM_PROPAGATION (coarse-grained) by default.
This method should be overridden if the argument reactToFineEvt
is set to true
in the constructor.
Otherwise, it executes propagate(PropagatorEventType.CUSTOM_PROPAGATION.getStrengthenedMask());
propagate
in class Propagator<IntVar>
item
- index of the variable var
in this
evtmask
- type of eventContradictionException
- if a contradiction occurspublic ESat isEntailed()
Propagator
this
is entailed according to the current state of its internal structure.
At least, should check the satisfaction of this
(when all is instantiated).isEntailed
in class Propagator<IntVar>
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