Function PROJECTION

• Defined in theory: Frame-ontology
• Source code: frame-ontology.lisp

Slots on this function:

Documentation:

The projection of an N-ary relation on column i is the class whose instances are the ith items of each tuple in the relation.

Arity: 3

Axioms:

(Nth-Domain Projection 3 Class)

(Nth-Domain Projection 2 Positive-Integer)

(<=> (Projection ?Relation ?Column ?Projection-Relation)
     (And (Defined (Arity ?Relation))
          (Positive-Integer ?Column)
          (=< ?Column (Arity ?Relation))
          (Class ?Projection-Relation)
          (Forall (?Projection-Instance)
                  (<=> (Instance-Of ?Instance ?Projection-Relation)
                       (Exists (?Tuple)
                               (And (Member ?Tuple ?Relation)
                                    (= (Nth ?Tuple ?Column)
                                       ?Instance)))))))