Blip Blog“Unfolding a T-box” may sound like some quaint tea ceremony ritual, but in fact in the context of description logics it refers to the iterative replacement of classes by equivalent anonymous class expressions. Many reasoners take advantage of T-box unfolding behind the scenes. But there may be reasons to unfold your T-box in a more [...]
My slides and paper for POSH are now online: Manuscript: owled2011_submission_15.pdf Slides: POSH (slideshare)
Posh (Prolog OWL Shell) is a command line utility that wraps the Thea OWL library to allow for advanced querying and processing of ontologies, combining the power of prolog and OWL reasoning. Installation Install SWI Download and install SWI-Prolog (http://swi-prolog.org). This is a simple point and click procedure for most platforms. If you want to [...]
Thea2 now wraps OWLAPI v3. Support is provided for pellet and hermit out of the box. There is now also additional command line support. download and install SWI-Prolog download Thea2 (for now you have to git clone and get the owlapi3 branch) Add Thea2 to your path: (assuming you install in ~/thea2) export PATH=”$PATH:$HOME/thea2″ You [...]
Provisional version of the paper up on: (new) Thea website (pending reivisions)
My invited talk from ICLP-2009 is available from slideshare: experiences-with-logic-programming-in-bioinformatics Unfortunately I didn’t get to go into detail in some sections, particularly Thea. Overall I had an excellent time, good to meet many LP luminaries and users.
The Thea OWL package is currently SWI-specific. It would be nice to use this with other prologs, particularly to take advantage of tabling in combination with DLP programs generated from OWL. I’m impressed by the prolog-commons effort, particularly the convergence we are seeing between Yap and Prolog. Currently the core parts of Thea work with [...]
Using the Thea2 library, it’ possible to translate certain OWL-DL ontologies into logic programs, and then query over them using LP systems such as Yap or XSB. Only the DLP subset is translated, and care must be taken to avoid common pitfalls. It’s now also possible to do the reverse translation for a similar subset [...]
The impedance mismatch problem is a well known one in mapping between an object-oriented language and a relational database. Tools such as Hibernate for Java make this easier for the ‘simple’ cases but can be awkward to use where one wants to take advantage of complex query processing within the DBMS. In contrast, prolog is [...]
Ontologies are vital for the life sciences. The Web Ontology Language (OWL) offers decidability of reasoning, and now with OWL2 and SWRL reasonably high levels of expressivity. Vangelis Vassilidis and I are writing Thea2, based on his original Thea library. The redesign introduces prolog predicates for every OWL2 axiom, and prolog terms for owl class [...]
