Package org.tweetyproject.arg.aba.syntax

Class AbaTheory<T extends Formula>

  • Type Parameters:
    T - is the type of the language that the ABA theory's rules range over
    All Implemented Interfaces:
    BeliefBase
    public class AbaTheory<T extends Formula>
extends java.lang.Object
implements BeliefBase
    An implementation of Assumption Based Argumentation.
    Author:
    Nils Geilen (geilenn@uni-koblenz.de)

    • Constructor Detail

      • AbaTheory

        public AbaTheory()

    • Method Detail

      • getAllDeductions

        public java.util.Collection<Deduction<T>> getAllDeductions()
        Returns:
        all deductions that can be derived from this theory

      • getAllDeductions

        public java.util.Collection<Deduction<T>> getAllDeductions​(java.util.Collection<Assumption<T>> assumptions)
        Parameters:
        assumptions - the set of assumptions used for the derivation
        Returns:
        all deductions that can be derived from this theory

      • getClosure

        public java.util.Collection<Assumption<T>> getClosure​(java.util.Collection<Assumption<T>> assumptions)
        A closure is the set of assumptions that can be derived from a set of assumptions via inference rules.
        Parameters:
        assumptions - a set of assumptions
        Returns:
        the closure of assumptions

      • isClosed

        public boolean isClosed​(java.util.Collection<Assumption<T>> assumptions)
        A set of assumptions is closed iff it equals its closure.
        Parameters:
        assumptions - a set of assumptions
        Returns:
        true iff the set of assumptions is closed under this argumentation theory

      • isFlat

        public boolean isFlat()
        An ABA theory is flat iff all subsets of its argumentation set are closed
        Returns:
        true iff the theory is flat

      • add

        public void add​(Formula rule)
        Parameters:
        rule - an assumption or an inference rule or a negation that is added to the theory

      • add

        public void add​(Formula... rules)
        Parameters:
        rules - assumptions or inference rules or negations that are added to the theory

      • addAssumption

        public void addAssumption​(T assumption)
        Parameters:
        assumption - a formula that is used as an assumption in the theory

      • addNegation

        public void addNegation​(T formula,
                        T negation)
        Adds a negation of form not formula = negation
        Parameters:
        formula - a formula
        negation - it's complement

      • negates

        public boolean negates​(T negation,
                       T formula)
        Checks whether the given two formulas are negations of each other
        Parameters:
        formula - a formula
        negation - a formula
        Returns:
        true iff the two formulas are negations of each other

      • attacks

        public boolean attacks​(Deduction<T> atter,
                       T atted)
        Parameters:
        atter - the attacking deduction
        atted - the attacked assumption
        Returns:
        true iff atter attacks atted

      • getRules

        public java.util.Collection<InferenceRule<T>> getRules()
        Returns:
        the rules

      • getAssumptions

        public java.util.Collection<Assumption<T>> getAssumptions()
        Returns:
        the assumptions

      • getNegations

        public java.util.Collection<Negation<T>> getNegations()
        Returns:
        the negations

      • setAssumptions

        public void setAssumptions​(java.util.Collection<Assumption<T>> assumptions)
        Parameters:
        assumptions - the assumptions to set

      • attacks

        public boolean attacks​(java.util.Collection<Assumption<T>> attackers,
                       java.util.Collection<Assumption<T>> attackeds)
        Checks whether a set of assumptions attacks another set of assumptions.
        Parameters:
        attackers - set of assumptions
        attackeds - set of assumptions
        Returns:
        true iff the first set of assumptions attacks the second set

      • defends

        public boolean defends​(java.util.Collection<Assumption<T>> defendor,
                       Assumption<T> defended)
        Checks whether a set of arguments defends an argument.
        Parameters:
        defendor - the defending set
        defended - the assumption which shall be defended
        Returns:
        true iff defendor defends defended

      • isConflictFree

        public boolean isConflictFree​(java.util.Collection<Assumption<T>> ext)
        Checks whether a set of arguments is conflict-free.
        Parameters:
        ext - a set of arguments
        Returns:
        true iff ext is conflict-free

      • getAllExtensions

        public java.util.Collection<java.util.Collection<Assumption<T>>> getAllExtensions()
        Computes all possible extensions.
        Returns:
        the powerset of the assumptions

      • getAllConflictFreeExtensions

        public java.util.Collection<java.util.Collection<Assumption<T>>> getAllConflictFreeExtensions()
        Computes all context-free extensions.
        Returns:
        all context-free extensions

      • isAdmissible

        public boolean isAdmissible​(AbaExtension<T> ext)
        Checks whether a set of arguments is admissible.
        Parameters:
        ext - the set
        Returns:
        true iff ext is admissible

      • getAllAdmissbleExtensions

        public java.util.Collection<AbaExtension<T>> getAllAdmissbleExtensions()
        Computes all admissible extensions.
        Returns:
        all admissible extensions

      • getMinimalSignature

        public Signature getMinimalSignature()
        Description copied from interface: BeliefBase
        Returns the signature of the language of this knowledge base.
        Specified by:
        getMinimalSignature in interface BeliefBase
        Returns:
        the signature of the language of this knowledge base.

      • asDungTheory

        public DungTheory asDungTheory()
        Returns:
        a Dung Theory derived from this ABA theory

      • toString

        public java.lang.String toString()
        Specified by:
        toString in interface BeliefBase
        Overrides:
        toString in class java.lang.Object