Package org.tweetyproject.lp.asp.syntax

Class ComparativeAtom

java.lang.Object
org.tweetyproject.lp.asp.syntax.ASPElement
org.tweetyproject.lp.asp.syntax.ASPBodyElement
org.tweetyproject.lp.asp.syntax.ComparativeAtom
All Implemented Interfaces:
Formula, ComplexLogicalFormula, LogicStructure, SimpleLogicalFormula
public class ComparativeAtom extends ASPBodyElement
This class represents a comparative atom, meaning an expression of the form 't x u' where t,u are terms and x is in {<, <=, ==, !=, >, >=}. Comparative atoms are called "Built-in atoms" in the ASP-Core-2 standard.
Author:
Tim Janus, Thomas Vengels, Anna Gessler

  • Constructor Details

    • ComparativeAtom

      public ComparativeAtom(ASPOperator.BinaryOperator op, Term<?> left, Term<?> right)
      Create a new comparative atom with the given operator and left and right term.
      Parameters:
      op - a binary operator
      left - term
      right - term

    • ComparativeAtom

      public ComparativeAtom(ComparativeAtom other)
      Copy-Constructor
      Parameters:
      other - another ComparativeAtom

  • Method Details

    • getLiterals

      public SortedSet<ASPLiteral> getLiterals()
      Description copied from class: ASPBodyElement
      Returns all literals in this element in form of a SortedSet. Literals are atoms or strict negations of atoms.
      Specified by:
      getLiterals in class ASPBodyElement
      Returns:
      all the literals used in the rule element

    • getPredicates

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

    • getAtoms

      public Set<ASPAtom> 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 ASPElement
      Returns:
      The set of all atoms

    • substitute

      public ComparativeAtom substitute(Term<?> t, Term<?> v)
      Description copied from interface: ComplexLogicalFormula
      Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
      Specified by:
      substitute in interface ComplexLogicalFormula
      Specified by:
      substitute in class ASPBodyElement
      Parameters:
      t - the term to be substituted.
      v - the term to substitute.
      Returns:
      a formula where every occurrence of "v" is replaced by "t".

    • getSignature

      public FolSignature getSignature()
      Description copied from interface: Formula
      Returns the signature of the language of this formula.
      Specified by:
      getSignature in interface Formula
      Specified by:
      getSignature in class ASPElement
      Returns:
      the signature of the language of this formula.

    • clone

      public ASPBodyElement 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 ASPElement
      Returns:
      the cloned formula

    • getPredicateCls

      public Class<? extends Predicate> getPredicateCls()
      Specified by:
      getPredicateCls in interface SimpleLogicalFormula
      Overrides:
      getPredicateCls in class ASPElement
      Returns:
      The class description of the predicate used by this formula.

    • isLiteral

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

    • getTerms

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

    • getOperator

      public ASPOperator.BinaryOperator getOperator()
      Returns:
      the comparative operator of the atom.

    • getLeft

      public Term<?> getLeft()
      Returns:
      the left (first) term of the comparative atom.

    • getRight

      public Term<?> getRight()
      Returns:
      the right (second) term of the comparative atom.

    • 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

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • printToDLV

      public String printToDLV()
      Description copied from class: ASPElement
      Returns a representation of this ASP element in DLV syntax. See http://www.dlvsystem.com/html/DLV_User_Manual.html for more information.
      Overrides:
      printToDLV in class ASPElement
      Returns:
      String representation in DLV syntax

    • hashCode

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

    • equals

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