Class Necessity

    • Constructor Detail

      • Necessity

        public Necessity​(RelationalFormula formula)
        Creates a new necessity formula with the given inner formula
        Parameters:
        formula - a formula, either a modal formula or a first-order formula.
    • Method Detail

      • substitute

        public FolFormula substitute​(Term<?> v,
                                     Term<?> t)
                              throws java.lang.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 FolFormula
        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 (NOTE: this exception is only thrown when "v" actually appears in this formula).
      • toNnf

        public FolFormula toNnf()
        Description copied from class: FolFormula
        Makes the negation normal form of this formula.
        Specified by:
        toNnf in class FolFormula
        Returns:
        the NNF of this formula
      • isDnf

        public boolean isDnf()
        Description copied from class: FolFormula
        Checks whether this formula is in disjunctive normal form.
        Specified by:
        isDnf in class FolFormula
        Returns:
        "true" iff this formula is in disjunctive normal form.
      • collapseAssociativeFormulas

        public RelationalFormula collapseAssociativeFormulas()
        Description copied from class: FolFormula
        This method collapses all associative operations appearing in this term, e.g. every a||(b||c) becomes a||b||c.
        Specified by:
        collapseAssociativeFormulas in class FolFormula
        Returns:
        the collapsed formula.