Package org.tweetyproject.lp.asp.syntax

Class Program

    • Constructor Summary

      Constructors 
      Constructor Description
      Program()
      Creates a new empty program.
      Program​(java.util.Collection<ASPRule> rules)
      Creates a new program with the given rules.
      Program​(ASPLiteral query, java.util.Set<ASPRule> rules)
      Creates a new program with the given query and rules.
      Program​(ASPRule... rules)
      Creates a new program with the given rules.
      Program​(Program other)
      Copy-Constructor

    • Method Summary

      Modifier and Type Method Description
      void add​(Program other)
      Adds another program's content to the content of this program.
      void addFact​(ASPLiteral fact)
      Adds a fact to this program.
      void addFact​(ClassicalHead fact)
      Adds the given fact to the program
      void addFacts​(ClassicalHead... fact)
      Adds the given facts to the program
      Program clone()  
      Program exchange​(Term<?> v, Term<?> t)
      Substitutes all occurrences of term "v" in this formula by term "t" and at the same time replaces all occurrences of term "t" by term "v" and eventually returns the new formula.
      static Program getDefaultification​(Program p)
      Creates the defaultification p_d of a given program p.
      FolSignature getMinimalSignature()
      Returns the signature of the language of this knowledge base.
      java.util.Set<Predicate> getOutputWhitelist()
      Returns the whitelist of predicates.
      ASPLiteral getQuery()
      Returns the query of the program, if there is one.
      Program getReduct​(java.util.Set<ASPLiteral> state)
      Returns the reduct of this program wrt.
      boolean hasQuery()
      Returns true if the program contains a query.
      boolean isExtendedProgram()
      Checks if the program is an extended program, meaning the heads of the literals do not have more than one literal.
      boolean isGround()
      Checks if the program is ground, meaning if it contains no rules with variables.
      boolean isSafe()
      Returns true if the program is safe, i.e.
      void setOutputWhitelist​(java.util.Collection<Predicate> ps)
      Sets the whitelist of predicates.
      void setQuery​(ASPLiteral query)
      Sets the query of the program.
      Program substitute​(java.util.Map<? extends Term<?>,​? extends Term<?>> map)
      Substitutes all occurrences of all terms "v" in map.keyset() in this formula by map.get(v) and returns the new formula.
      Program substitute​(Term<?> v, Term<?> t)
      Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
      java.lang.String toString()  

      • Methods inherited from class java.util.HashSet

        add, clear, contains, isEmpty, iterator, remove, size, spliterator

      • Methods inherited from class java.util.AbstractSet

        equals, hashCode, removeAll

      • Methods inherited from class java.util.AbstractCollection

        addAll, containsAll, retainAll, toArray, toArray

      • Methods inherited from class java.lang.Object

        getClass, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.util.Collection

        parallelStream, removeIf, stream, toArray

      • Methods inherited from interface java.lang.Iterable

        forEach

      • Methods inherited from interface java.util.Set

        addAll, containsAll, equals, hashCode, removeAll, retainAll, toArray, toArray

    • Constructor Detail

      • Program

        public Program()
        Creates a new empty program.

      • Program

        public Program​(java.util.Collection<ASPRule> rules)
        Creates a new program with the given rules.
        Parameters:
        rules - a set of rules

      • Program

        public Program​(ASPRule... rules)
        Creates a new program with the given rules.
        Parameters:
        rules - a set of rules

      • Program

        public Program​(ASPLiteral query,
               java.util.Set<ASPRule> rules)
        Creates a new program with the given query and rules.
        Parameters:
        query - a query
        rules - a set of rules

      • Program

        public Program​(Program other)
        Copy-Constructor
        Parameters:
        other - another program

    • Method Detail

      • setQuery

        public void setQuery​(ASPLiteral query)
        Sets the query of the program.
        Parameters:
        query - a literal

      • setOutputWhitelist

        public void setOutputWhitelist​(java.util.Collection<Predicate> ps)
        Sets the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.
        Parameters:
        ps - set of predicates

      • getOutputWhitelist

        public java.util.Set<Predicate> getOutputWhitelist()
        Returns the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.
        Returns:
        set of whitelisted predicates

      • hasQuery

        public boolean hasQuery()
        Returns true if the program contains a query.
        Returns:
        true if the program has a query, false otherwise

      • getQuery

        public ASPLiteral getQuery()
        Returns the query of the program, if there is one.
        Returns:
        a literal, or null if the program has no query

      • addFact

        public void addFact​(ASPLiteral fact)
        Adds a fact to this program.
        Parameters:
        fact - a literal

      • add

        public void add​(Program other)
        Adds another program's content to the content of this program.
        Parameters:
        other - Reference to the other program.

      • isExtendedProgram

        public boolean isExtendedProgram()
        Checks if the program is an extended program, meaning the heads of the literals do not have more than one literal.
        Returns:
        True if the program is an extended program, false otherwise.

      • isSafe

        public boolean isSafe()
        Returns true if the program is safe, i.e. if all of its rules and its query are safe according to the definition of safety given in the ASP-Core-2 standard.
        Returns:
        true if the program is safe, false otherwise

      • isGround

        public boolean isGround()
        Checks if the program is ground, meaning if it contains no rules with variables.
        Returns:
        true if the program is ground, false otherwise

      • substitute

        public Program substitute​(Term<?> v,
                          Term<?> t)
                   throws java.lang.IllegalArgumentException
        Description copied from interface: LogicProgram
        Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
        Specified by:
        substitute in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
        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:
        java.lang.IllegalArgumentException - if "v" and "t" are of different sorts

      • substitute

        public Program substitute​(java.util.Map<? extends Term<?>,​? extends Term<?>> map)
                   throws java.lang.IllegalArgumentException
        Description copied from interface: LogicProgram
        Substitutes all occurrences of all terms "v" in map.keyset() in this formula by map.get(v) and returns the new formula.
        Specified by:
        substitute in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
        Parameters:
        map - a mapping defining which terms to be substituted.
        Returns:
        a formula where every term in map.keyset() has been replaced by map.get(v).
        Throws:
        java.lang.IllegalArgumentException - if any term and its mapping are of different sorts

      • exchange

        public Program exchange​(Term<?> v,
                        Term<?> t)
                 throws java.lang.IllegalArgumentException
        Description copied from interface: LogicProgram
        Substitutes all occurrences of term "v" in this formula by term "t" and at the same time replaces all occurrences of term "t" by term "v" and eventually returns the new formula.
        Specified by:
        exchange in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
        Parameters:
        v - a term.
        t - a term.
        Returns:
        a new logical formula with both "v" and "t" exchanged.
        Throws:
        java.lang.IllegalArgumentException - if "v" and "t" are of different sorts

      • clone

        public Program clone()
        Overrides:
        clone in class java.util.HashSet<ASPRule>

      • getReduct

        public Program getReduct​(java.util.Set<ASPLiteral> state)
        Returns the reduct of this program wrt. the given state, i.e. a program that contains no default negation and only those rules of this program (without all default-negated literals in the body) that do not have a default-negated version of a literal in their body.
        Parameters:
        state - some set of literals
        Returns:
        the reduct of this program

      • getDefaultification

        public static Program getDefaultification​(Program p)
        Creates the defaultification p_d of a given program p. A defaultificated program p' of p adds for every Rule r in p a modified rule r_d of the form: 'H(r) :- B(r), not -H(r).' to the program p'.
        Parameters:
        p - The program which is not defaultificated yet
        Returns:
        a program p' which is the defaultificated version of p.