ANN: Thea OWL library for SWI Prolog v0.4

A Web Ontology Language - OWL Library
for [SWI] Prolog.

/Vangelis Vassiliadis

*Thea* is a Prolog library for manipulating OWL (Web Ontology Language)
content. *Thea* version 0.4 consists of:

    * Thea OWL parser and
    * Thea OWL generator.

Thea OWL parser uses SWI-Prolog <>’s Semantic
Web library for parsing RDF/XML serialisations of OWL documents into RDF
triples and then it builds a representation of the OWL ontology as it is
defined in the OWL Web Ontology Language Semantics and Abstract Syntax
<> part of the OWL
specification. The OWL ontology abstract syntax is implemented as Prolog

*Thea* has been tested extensively against the OWL test cases and for
almost all cases it generates the correct syntactic constructs.

*Thea* OWL generator is used to convert the OWL absract syntax
constructs from Prolog terms into RDF triples and saving the resulting
RDF model into an RDF/XML file. Thea OWL generator is also using
SWI-Prolog <>’s Semantic Web library for
saving RDF models into RDF/XML files.

Current version of *Thea* OWL Prolog library (v 0.4) released September
29, 2005. *Thea* is developed by Vangelis Vassiliadis
<> and is available under the GNU/GPL license.

*Version 0.4 Changes: *

    * use of SWI's rdf parser 5.5.12
    * rdf_load/2 options to noshare of blank nodes and use a convert
      function to hold datatyped values.
    * removed fix_owl. Apparently is not needed with SWI 5.5.x
    * Implemented equivalentProperties by re-using the logic of
      equivalentClass and sameAs.
    * Implementation of owl:imports (handled at RDF/triple level) by
      importing all RDF triples prior to building the OWL abstract
      syntax terms. Flag to select if imports will be handled.
    * OWL parser can parse now either local files or URLs (in-line with
      Semweb's package RDF parser). Use of SWI's http package.
    * owl_pack_ontology, owl_report added as top-level predicates for
      future manipulation of Ontologies in Abstract Syntax form.

*Known issues and limitations:*

    * *Thea* v.0.4 is not a reasoner: it does not make any inferences
      nor it checks the consistency of the resulted OWL ontology.
    * *Thea* parses all ‘versions’ of OWL ontologies (Full/DL/Lite) but
      does it is not currently a ‘species’ validator.
    * The value of an individual is not tested for structure sharing.

Thea OWL Parser for SWI Prolog library
Thea OWL Generator for SWI Prolog library
Documentation <>

Please send me <> any comments and


Received on Thursday, 29 September 2005 21:17:34 UTC