net.sf.tweety.logics.pl.syntax

Class Disjunction

java.lang.Object

net.sf.tweety.logics.pl.syntax.PropositionalFormula

net.sf.tweety.logics.pl.syntax.AssociativePropositionalFormula

net.sf.tweety.logics.pl.syntax.Disjunction

All Implemented Interfaces:

java.lang.Iterable<PropositionalFormula>, java.util.Collection<PropositionalFormula>, java.util.List<PropositionalFormula>, Formula, AssociativeFormulaSupport.AssociativeSupportBridge, AssociativeFormula<PropositionalFormula>, ClassicalFormula, Conjuctable, Disjunctable, Invertable, ProbabilityAware, SimpleLogicalFormula

public class Disjunction
extends AssociativePropositionalFormula

This class represents a disjunction in propositional logic.

Author:

Matthias Thimm, Tim Janus

Field Summary

Fields inherited from class net.sf.tweety.logics.pl.syntax.AssociativePropositionalFormula

support

Constructor Summary

Constructors

Constructor and Description
Disjunction() Creates a new (empty) disjunction.
Disjunction(java.util.Collection<? extends PropositionalFormula> formulas) Creates a new disjunction with the given inner formulas.
Disjunction(PropositionalFormula first, PropositionalFormula second) Creates a new disjunction with the two given formulae

Method Summary

Modifier and Type	Method and Description
PropositionalFormula	clone() Creates a deep copy of this formula
PropositionalFormula	collapseAssociativeFormulas() This method collapses all associative operations appearing in this term, e.g.
Disjunction	createEmptyFormula()
java.lang.String	getEmptySymbol()
java.util.Set<PossibleWorld>	getModels(PropositionalSignature sig) Returns the set of models of this formula wrt.
java.lang.String	getOperatorSymbol()
PropositionalFormula	replace(Proposition p, PropositionalFormula f, int i) Replaces the ith instance of the proposition p by f.
Conjunction	toCnf() This method returns this formula in conjunctive normal form (CNF).
PropositionalFormula	toNnf() This method returns this formula in negation normal form (NNF).
PropositionalFormula	trim() Removes duplicates (identical formulas) from conjunctions and disjunctions and duplicate negations.

Methods inherited from class net.sf.tweety.logics.pl.syntax.AssociativePropositionalFormula

add, add, addAll, addAll, clear, contains, containsAll, createEmptySignature, equals, get, getAtoms, getFormulas, getFormulas, getLiterals, getPredicates, getSignature, hashCode, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, numberOfOccurrences, remove, remove, removeAll, retainAll, set, size, subList, toArray, toArray, toString

Methods inherited from class net.sf.tweety.logics.pl.syntax.PropositionalFormula

combineWithAnd, combineWithOr, complement, getModels, getPredicateCls, getPrimeImplicants, getUniformProbability, isConjunctiveClause, isLiteral, resolvableWith, resolveWith, toBlakeCanonicalForm, toDnf

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.sf.tweety.logics.commons.syntax.interfaces.SimpleLogicalFormula

getPredicateCls, isLiteral

Methods inherited from interface java.util.List

replaceAll, sort, spliterator

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

Disjunction

public Disjunction(java.util.Collection<? extends PropositionalFormula> formulas)

Creates a new disjunction with the given inner formulas.

Parameters:

formulas - a collection of formulas.

Disjunction

public Disjunction()

Creates a new (empty) disjunction.

Disjunction

public Disjunction(PropositionalFormula first,
                   PropositionalFormula second)

Creates a new disjunction with the two given formulae

Parameters:

first - a propositional formula.

second - a propositional formula.

Method Detail

collapseAssociativeFormulas

public PropositionalFormula collapseAssociativeFormulas()

Description copied from class: PropositionalFormula

This method collapses all associative operations appearing in this term, e.g. every a||(b||c) becomes a||b||c.

Specified by:

collapseAssociativeFormulas in class PropositionalFormula

Returns:

the collapsed formula.

toNnf

public PropositionalFormula toNnf()

Description copied from class: PropositionalFormula

This method returns this formula in negation normal form (NNF). A formula is in NNF iff negations occur only directly in front of a proposition.

Specified by:

toNnf in class PropositionalFormula

Returns:

the formula in NNF.

clone

public PropositionalFormula clone()

Description copied from interface: SimpleLogicalFormula

Creates a deep copy of this formula

Specified by:

clone in interface SimpleLogicalFormula

Specified by:

clone in class PropositionalFormula

createEmptyFormula

public Disjunction createEmptyFormula()

Returns:

an empty version of the AssociativeFormula

getOperatorSymbol

public java.lang.String getOperatorSymbol()

Returns:

A String representing the operator which connects two items of the associative formula.

getEmptySymbol

public java.lang.String getEmptySymbol()

Returns:

A String representing an empty version of the Associative Formula implementation

toCnf

public Conjunction toCnf()

Description copied from class: PropositionalFormula

This method returns this formula in conjunctive normal form (CNF). A formula is in CNF iff it is a conjunction of disjunctions and in NNF.

Specified by:

toCnf in class PropositionalFormula

Returns:

the formula in CNF.

trim

public PropositionalFormula trim()

Description copied from class: PropositionalFormula

Removes duplicates (identical formulas) from conjunctions and disjunctions and duplicate negations.

Specified by:

trim in class PropositionalFormula

Returns:

an equivalent formula without duplicates.

getModels

public java.util.Set<PossibleWorld> getModels(PropositionalSignature sig)

Description copied from class: PropositionalFormula

Returns the set of models of this formula wrt. the given signature.

Specified by:

getModels in class PropositionalFormula

Parameters:

sig - some propositional signature

Returns:

the set of models of this formula wrt. the given signature.

replace

public PropositionalFormula replace(Proposition p,
                                    PropositionalFormula f,
                                    int i)

Description copied from class: PropositionalFormula

Replaces the ith instance of the proposition p by f.

Specified by:

replace in class PropositionalFormula

Parameters:

p - some proposition

f - some formula

i - the index of the proposition

Returns:

a new formula with the ith instance of the proposition p replaced by f.