org.chocosolver.solver.learn

Class Implications

java.lang.Object

org.chocosolver.solver.learn.Implications

Direct Known Subclasses:

LazyImplications

public abstract class Implications
extends Object

A abstract class that maintains an implication graph, built from events generated thanks to the propagation.

Project: choco-solver.

Since:

25/01/2017.

Author:

Charles Prud'homme

Constructor Summary

Constructors

Constructor and Description
Implications()

Method Summary

Modifier and Type	Method and Description
abstract void	collectNodesFromConflict(ContradictionException conflict, ValueSortedMap<IntVar> front) Fill set with indices of nodes that throws the conflict
abstract void	copyComplementSet(IntVar var, IntIterableRangeSet set, IntIterableRangeSet dest) Copy in dest the complement of set wrt to root domain of var
abstract void	findPredecessor(ValueSortedMap<IntVar> front, IntVar vi, int p) Find the direct predecessor of a node, declared on variable vi, starting from node at position p.
abstract ICause	getCauseAt(int idx) Get the ICause declared in node idx
abstract IntIterableRangeSet	getDomainAt(int idx) Get the IntIterableRangeSet that represents domain declared in node idx
abstract int	getEventMaskAt(int idx) Get the mask of event declared in node idx.
abstract IntVar	getIntVarAt(int idx) Get the IntVar declared in node idx
abstract int	getPredecessorOf(int idx) Get the position of precedent entry of the one declared in node idx
abstract IntIterableRangeSet	getRootDomain(IntVar var) Get the IntIterableRangeSet that represents domain of this variables as declared in the model
abstract int	getValueAt(int idx) Get the value declared in node idx
abstract void	init(Model model) Initialize this class
abstract void	predecessorsOf(int p, ValueSortedMap<IntVar> front) Retrieve the nodes that are predecessors of node p in this and put them into set.
abstract void	pushEvent(IntVar var, ICause cause, IntEventType mask, int one, int two, int three) Push an event
abstract void	reset() Reset the model, set at its creation state, before calling init(Model).
abstract int	size()
abstract void	undoLastEvent() Undo the last event stored, use only when dealing with views.

Methods inherited from class java.lang.Object

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

Constructor Detail

Implications

public Implications()

Method Detail

init

public abstract void init(Model model)

Initialize this class

Parameters:

model - if needed, a reference to the model that uses this class

reset

public abstract void reset()

Reset the model, set at its creation state, before calling init(Model).

pushEvent

public abstract void pushEvent(IntVar var,
                               ICause cause,
                               IntEventType mask,
                               int one,
                               int two,
                               int three)

Push an event

Parameters:

var - modified variable

cause - cause of the modification

mask - modification mask

one - an int

two - an int

three - an int

size

public abstract int size()

Returns:

the number of nodes in the implication graph.

collectNodesFromConflict

public abstract void collectNodesFromConflict(ContradictionException conflict,
                                              ValueSortedMap<IntVar> front)

Fill set with indices of nodes that throws the conflict

Parameters:

conflict - the failure, in the form of a ContradictionException

front - (initially empty) map of (node, variable) in conflict

predecessorsOf

public abstract void predecessorsOf(int p,
                                    ValueSortedMap<IntVar> front)

Retrieve the nodes that are predecessors of node p in this and put them into set.

Parameters:

p - index of the node whom predecessors have to be found

front - map of (node, variable) in conflict

findPredecessor

public abstract void findPredecessor(ValueSortedMap<IntVar> front,
                                     IntVar vi,
                                     int p)

Find the direct predecessor of a node, declared on variable vi, starting from node at position p.

Parameters:

front - the set to update

vi - the variable to look the predecessor for

p - the rightmost position of the node (below means outdated node).

getCauseAt

public abstract ICause getCauseAt(int idx)

Get the ICause declared in node idx

Parameters:

idx - position of the node to query

Returns:

the cause declared in node idx

getEventMaskAt

public abstract int getEventMaskAt(int idx)

Get the mask of event declared in node idx. The mask can be a bitwise operation over mask of IntEventType.

Parameters:

idx - position of the node to query

Returns:

the event declared in node idx

getIntVarAt

public abstract IntVar getIntVarAt(int idx)

Get the IntVar declared in node idx

Parameters:

idx - position of the node to query

Returns:

the intvar declared in node idx

getValueAt

public abstract int getValueAt(int idx)

Get the value declared in node idx

Parameters:

idx - position of the node to query

Returns:

the value declared in node idx

getDomainAt

public abstract IntIterableRangeSet getDomainAt(int idx)

Get the IntIterableRangeSet that represents domain declared in node idx

Parameters:

idx - position of the node to query

Returns:

the domain declared in node idx

getPredecessorOf

public abstract int getPredecessorOf(int idx)

Get the position of precedent entry of the one declared in node idx

Parameters:

idx - position of the node to query

Returns:

its ancestor

getRootDomain

public abstract IntIterableRangeSet getRootDomain(IntVar var)

Get the IntIterableRangeSet that represents domain of this variables as declared in the model

Parameters:

var - variable to query

Returns:

the domain declared in node idx

copyComplementSet

public abstract void copyComplementSet(IntVar var,
                                       IntIterableRangeSet set,
                                       IntIterableRangeSet dest)

Copy in dest the complement of set wrt to root domain of var

Parameters:

var - variable to query

undoLastEvent

public abstract void undoLastEvent()

Undo the last event stored, use only when dealing with views.