EL++ Implementation Notes

Below is a summary of the Arity/Prolog term form of EL++ that we have implemented (including Prolog operator definitions).


  Role inclusion                     R1 @< R2                              op(700,xfx)

  Role equality                       R1 @= R2                              op(700,xfx) (nonstd op)

  Concept inclusion              C1 < C2                  op(600,xfx)

  Concept equality                C1 = C2                  op(700,xfy)


Role operator:

  Composition                        *                                              R1 * R2 (uses std op(400,yfx))


Concept operators:

  Conjunction                        list                                           [C1, ... Cn]

  Existential                            e(R,C)                    

  Top                                       '$t'

  Bottom                 '$b'

  Nominal                               n(I)                                          (singleton name for non-unique individual)

  Concrete                             cc(T)                                       Term is for concrete concept (NYI)


ABox assertions:

  Concept                               Nom << Concept  op(550,yfx)

  Role                                      r(Role,Nom1,Nom2)




More information on Ontologies and DLs may be found at the following sites:

The DL Home Page


The DAML Home Page


The Semantic Web Home Page


The International Conference on Automated Reasoning with Analytic Tableaux and Related Methods


The Laboratory for Applied Ontology



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