Package net.sf.tweety.commons.util.rules

Class Derivation<T extends Rule<?,​?>>

  • Type Parameters:
    T - the specific rule class
    All Implemented Interfaces:
    Serializable, Cloneable, Iterable<T>, Collection<T>, List<T>, RandomAccess
    public class Derivation<T extends Rule<?,​?>>
extends ArrayList<T>
    This class models a derivation, i.e. a minimal (with respect to set inclusion) sequence of rules [R1, ... ,Rn] such that for any Ri and for any p in the premise of Ri there is an Rj with j > i and the conclusion of Rj equals p.
    Author:
    Matthias Thimm
    See Also:
    Serialized Form

    • Constructor Detail

      • Derivation

        public Derivation​(List<T> rules)
        Creates a new derivation with the given sequence of rules.
        Parameters:
        rules - a sequence of rules.

    • Method Detail

      • getConclusion

        public Formula getConclusion()
        Returns the conclusion of this derivation.
        Returns:
        the conclusion of this derivation.

      • allDerivations

        public static <S extends Rule<?,​?>> Set<Derivation<S>> allDerivations​(Collection<? extends S> rules)
        Returns the set of all possible derivations from the set of rules.
        Type Parameters:
        S - the type of rules
        Parameters:
        rules - a set of rules
        Returns:
        the set of all possible derivations

      • allDerivations

        public static <S extends Rule<?,​?>> Set<Derivation<S>> allDerivations​(Collection<? extends S> rules,
                                                                            Formula conclusion)
        Returns the set of all possible derivations with the given conclusion from the set of rules.
        Type Parameters:
        S - the type of rules
        Parameters:
        rules - a set of rules
        conclusion - the conclusion
        Returns:
        the set of all possible derivations with the given conclusion

      • isFounded

        public boolean isFounded()
        Checks whether this derivation is founded, i.e. whether every formula appearing in the premise of a rule is also the conclusion of a previous rule.
        Returns:
        "true" if this derivation is founded.

      • isMinimal

        public boolean isMinimal()
        Checks whether this derivation is minimal with respect to set inclusion. This is equivalent to checking whether every conclusion besides the first is used in a premise and no conclusion appear twice.
        Returns:
        "true" if this derivation is minimal.