Package org.tweetyproject.logics.rdl.syntax

Class DefaultRule

java.lang.Object
org.tweetyproject.logics.commons.syntax.RelationalFormula
org.tweetyproject.logics.rdl.syntax.DefaultRule
All Implemented Interfaces:
Formula, ClassicalFormula, ComplexLogicalFormula, Conjunctable, Disjunctable, Invertable, LogicStructure, ProbabilityAware, QuantifiedFormula, SimpleLogicalFormula
public class DefaultRule extends RelationalFormula
Models a default rule 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 Details

  • Method Details

    • isNormal

      public boolean isNormal​(DefaultTheory dt)
      Tests, whether the default is normal normal ^= a:c/c
      Parameters:
      dt - a default theory
      Returns:
      true iff the theory is normal

    • getPrerequisite

      public FolFormula getPrerequisite()
      Returns:
      the default's prerequisite

    • getJustification

      public Collection<FolFormula> getJustification()
      Returns:
      the default's justification

    • getConclusion

      public FolFormula getConclusion()
      Returns:
      the default's conclusion

    • getPredicates

      public Set<? extends Predicate> getPredicates()
      Description copied from interface: SimpleLogicalFormula
      Processes the set of all predicates which appear in this formula
      Returns:
      all predicates that appear in this formula

    • isLiteral

      public boolean isLiteral()
      Returns:
      true if the formula represents a literal in the language or false otherwise

    • getQuantifierVariables

      public Set<Variable> getQuantifierVariables()
      Returns:
      a set containing all quantified variables

    • getUnboundVariables

      public Set<Variable> getUnboundVariables()
      Returns:
      a set of of unbound variables

    • containsQuantifier

      public boolean containsQuantifier()
      Description copied from interface: QuantifiedFormula
      Checks whether this formula contains any quantification.
      Returns:
      "true" if this formula contains a quantification.

    • isWellBound

      public boolean isWellBound()
      Description copied from interface: QuantifiedFormula
      Checks whether this formula is well-bound, i.e. whether no variable bound by a quantifier is again bound by another quantifier within the first quantifier's range.
      Returns:
      "true" if this formula is well-bound, "false" otherwise.

    • isWellBound

      public boolean isWellBound​(Set<Variable> boundVariables)
      Description copied from interface: QuantifiedFormula
      Checks whether this formula is well-bound, i.e. whether no variable bound by a quantifier is again bound by another quantifier within the first quantifier range. Every variable in "boundVariables" is assumed to be bound already.
      Parameters:
      boundVariables - the variables assumed to be bound.
      Returns:
      "true" if this formula is well-bound, "false" otherwise.

    • isClosed

      public boolean isClosed()
      Description copied from interface: QuantifiedFormula
      Checks whether this formula is closed, i.e. whether every variables occurring in the formula is bound by a quantifier.
      Returns:
      "true" if this formula is closed, "false" otherwise.

    • isClosed

      public boolean isClosed​(Set<Variable> boundVariables)
      Description copied from interface: QuantifiedFormula
      Checks whether this formula is closed, i.e. whether every variables occurring in the formula is bound by a quantifier. Every variable in "boundVariables" is already assumed to be bound.
      Parameters:
      boundVariables - the variables assumed to be bound.
      Returns:
      "true" if this formula is closed wrt. "boundVariables", "false" otherwise.

    • getTerms

      public Set<Term<?>> getTerms()
      Returns:
      a set containing all terms of this logical structure

    • getTerms

      public <C extends Term<?>> Set<C> getTerms​(Class<C> cls)
      Description copied from interface: LogicStructure
      Processes the set containing all terms of type C. This method uses the equals method of the given Class and therefore does not add terms which are sub classes of type C to the set.
      Type Parameters:
      C - the type of terms
      Parameters:
      cls - The Class structure containing type information about the searched term
      Returns:
      A set containing all terms of type C of this logical structure

    • getAtoms

      public Set<FolAtom> getAtoms()
      Description copied from interface: SimpleLogicalFormula
      Processes the set of all atoms which appear in this formula
      Specified by:
      getAtoms in interface SimpleLogicalFormula
      Specified by:
      getAtoms in class RelationalFormula
      Returns:
      all atoms that appear in this formula.

    • getFunctors

      public Set<Functor> getFunctors()
      Specified by:
      getFunctors in class RelationalFormula
      Returns:
      all functors that appear in this formula.

    • substitute

      public RelationalFormula substitute​(Term<?> v, Term<?> t) throws IllegalArgumentException
      Description copied from class: RelationalFormula
      Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula. NOTE: if "v" is a variable and bound to a quantifier then "v" is not substituted in that quantifiers inner formula.
      Specified by:
      substitute in interface ComplexLogicalFormula
      Specified by:
      substitute in class RelationalFormula
      Parameters:
      v - the term to be substituted.
      t - the term to substitute.
      Returns:
      a formula where every occurrence of "v" is replaced by "t".
      Throws:
      IllegalArgumentException - if "v" and "t" are of different sorts (NOTE: this exception is only thrown when "v" actually appears in this formula).

    • getUniformProbability

      public Probability getUniformProbability()
      Specified by:
      getUniformProbability in interface ProbabilityAware
      Specified by:
      getUniformProbability in class RelationalFormula
      Returns:
      this formula's probability in the uniform distribution.

    • complement

      public RelationalFormula complement()
      Specified by:
      complement in interface Invertable
      Specified by:
      complement in class RelationalFormula
      Returns:
      the complement of this formula.

    • combineWithOr

      public Disjunction combineWithOr​(Disjunctable formula)
      Specified by:
      combineWithOr in interface Disjunctable
      Specified by:
      combineWithOr in class RelationalFormula
      Parameters:
      formula - a formula to be combined with OR and this.
      Returns:
      a disjunction of this and the given formula.

    • combineWithAnd

      public Conjunction combineWithAnd​(Conjunctable formula)
      Description copied from interface: Conjunctable
      Returns a conjunction of this and the given formula.
      Specified by:
      combineWithAnd in interface Conjunctable
      Specified by:
      combineWithAnd in class RelationalFormula
      Parameters:
      formula - a formula to be combined with AND and this.
      Returns:
      a conjunction of this and the given formula.

    • getSignature

      public FolSignature getSignature()
      Description copied from interface: Formula
      Returns the signature of the language of this formula.
      Returns:
      the signature of the language of this formula.

    • toString

      public String toString()
      Specified by:
      toString in class RelationalFormula

    • clone

      public RelationalFormula clone()
      Description copied from interface: SimpleLogicalFormula
      Creates a deep copy of this formula
      Specified by:
      clone in interface ComplexLogicalFormula
      Specified by:
      clone in interface SimpleLogicalFormula
      Specified by:
      clone in class RelationalFormula
      Returns:
      the cloned formula

    • hashCode

      public int hashCode()
      Specified by:
      hashCode in interface SimpleLogicalFormula
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals​(Object o)
      Specified by:
      equals in interface SimpleLogicalFormula
      Overrides:
      equals in class Object