net.sf.tweety.logics.cl

Class RuleBasedCReasoner

java.lang.Object

net.sf.tweety.commons.Reasoner

net.sf.tweety.logics.cl.RuleBasedCReasoner

public class RuleBasedCReasoner
extends Reasoner

This is a reasoner using c-representation and rules to solve these c-representations. It contains a list of rules whereby the first rule is the rule with the highest priorization, that means it is applied first.

Author:

Tim Janus

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	RuleBasedCReasoner.Rule A rule that is applicable by the RuleBasedCReasoner to reason a c-representation given a conditional belief base.

Field Summary

Fields

Modifier and Type	Field and Description
private ClBeliefSet	beliefBase the belief base that is reasoned on
private ConditionalStructure	cs the conditional structure generated by the belief base of this reasoner, is null until prepare() is called.
private boolean	humanFriendly a flag indicating if a human friend processing shall be used, that means everything is calculated no fast-evaluation, such that a human can better follow the algorithm.
private java.util.Map<Conditional,KappaValue>	kappas the map of conditions to their penalty values (kappa), is null until prepare() is called
private RankingFunction	rfunc The ranking function representing the c-representation of the given belief base, is null until process() returns true
private java.util.List<RuleBasedCReasoner.Rule>	rules A prioritized list of rules, the first rule is applied first and so on.

Constructor Summary

Constructors

Constructor and Description
RuleBasedCReasoner(ClBeliefSet beliefBase)
RuleBasedCReasoner(ClBeliefSet beliefBase, boolean humanFriendly)
RuleBasedCReasoner(java.util.Collection<Conditional> conditionals)
RuleBasedCReasoner(java.util.Collection<Conditional> conditionals, boolean humanFriendly)

Method Summary

Modifier and Type	Method and Description
ConditionalStructure	getConditionalStructure()
java.util.Collection<KappaValue>	getKappas()
RankingFunction	getSemantic()
boolean	isComplete() Checks every kappa value.
void	prepare() Prepares the data structures: ConditionalStructure and the list of KappaValue, such that the rules can be applied on them.
boolean	process() Processes the kappa values using the rules stored in the prioritzed rule list.
Answer	query(Formula query) This method determines the answer of the given query wrt.

Methods inherited from class net.sf.tweety.commons.Reasoner

getKnowledgeBase

Methods inherited from class java.lang.Object

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

Field Detail

beliefBase

private ClBeliefSet beliefBase

the belief base that is reasoned on

cs

private ConditionalStructure cs

the conditional structure generated by the belief base of this reasoner, is null until prepare() is called.

kappas

private java.util.Map<Conditional,KappaValue> kappas

the map of conditions to their penalty values (kappa), is null until prepare() is called

rfunc

private RankingFunction rfunc

The ranking function representing the c-representation of the given belief base, is null until process() returns true

humanFriendly

private boolean humanFriendly

a flag indicating if a human friend processing shall be used, that means everything is calculated no fast-evaluation, such that a human can better follow the algorithm.

rules

private java.util.List<RuleBasedCReasoner.Rule> rules

A prioritized list of rules, the first rule is applied first and so on. If a progress is caused by applying the rule then the first rule is applied next again.

Constructor Detail

RuleBasedCReasoner

public RuleBasedCReasoner(java.util.Collection<Conditional> conditionals)

RuleBasedCReasoner

public RuleBasedCReasoner(java.util.Collection<Conditional> conditionals,
                          boolean humanFriendly)

RuleBasedCReasoner

public RuleBasedCReasoner(ClBeliefSet beliefBase)

RuleBasedCReasoner

public RuleBasedCReasoner(ClBeliefSet beliefBase,
                          boolean humanFriendly)

Method Detail

getSemantic

public RankingFunction getSemantic()

Returns:

the c-representation of the belief base as a ranking function

process

public boolean process()

Processes the kappa values using the rules stored in the prioritzed rule list. It applies the rules by their priority until no changes occurred after every rule is applied.

Returns:

true if the processing of the kappa values is complete, false if it is not complete.

isComplete

public boolean isComplete()

Checks every kappa value.

Returns:

true if every kappa value is evaluated, false otherwise

prepare

public void prepare()

Prepares the data structures: ConditionalStructure and the list of KappaValue, such that the rules can be applied on them.

getKappas

public java.util.Collection<KappaValue> getKappas()

Returns:

An unmodifiable list containing the kappa values used by the reasoner or null if the reasoner is not prepared yet

getConditionalStructure

public ConditionalStructure getConditionalStructure()

Returns:

The conditional structure used by the reasoner or null if the reasoner is not prepared yet

query

public Answer query(Formula query)

Description copied from class: Reasoner

This method determines the answer of the given query wrt. to the given knowledge base.

Specified by:

query in class Reasoner

Parameters:

query - a query.

Returns:

the answer to the query.