net.sf.tweety.logics.rdl

Class DefaultTheory

java.lang.Object

net.sf.tweety.logics.rdl.DefaultTheory

All Implemented Interfaces:

net.sf.tweety.commons.BeliefBase

public class DefaultTheory
extends Object
implements net.sf.tweety.commons.BeliefBase

Models a default theory in Reiter's default logic, see [R. Reiter. A logic for default reasoning. Artificial Intelligence, 13:81–132, 1980].

Author:

Matthias Thimm, Nils Geilen

Constructor Summary

Constructors

Constructor and Description
DefaultTheory() constructs empty default theory
DefaultTheory(net.sf.tweety.logics.fol.FolBeliefSet facts, Collection<DefaultRule> defaults) constructs a default theory from a knowledge base and a set of defaults

Method Summary

Modifier and Type	Method and Description
Collection<DefaultRule>	getDefaults()
net.sf.tweety.logics.fol.FolBeliefSet	getFacts()
net.sf.tweety.commons.Signature	getSignature()
DefaultTheory	ground() Removes Variables by expanding formulas
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultTheory

public DefaultTheory()

constructs empty default theory

DefaultTheory

public DefaultTheory(net.sf.tweety.logics.fol.FolBeliefSet facts,
                     Collection<DefaultRule> defaults)

constructs a default theory from a knowledge base and a set of defaults

Parameters:

facts - the knowledge base

defaults - the defaults

Method Detail

getDefaults

public Collection<DefaultRule> getDefaults()

Returns:

all the default rules

ground

public DefaultTheory ground()

Removes Variables by expanding formulas

Returns:

grounded version of the default theory

getSignature

public net.sf.tweety.commons.Signature getSignature()

Specified by:

getSignature in interface net.sf.tweety.commons.BeliefBase

toString

public String toString()

Specified by:

toString in interface net.sf.tweety.commons.BeliefBase

Overrides:

toString in class Object

getFacts

public net.sf.tweety.logics.fol.FolBeliefSet getFacts()

Returns:

FoL formulas in default theories