Omega Ontology: Programmatic API

Beginning with the Omega 3 release, all data are accessed via the PowerLoom description logic system. In particular, we take advantage of PowerLoom's persistent storage mechanism. Persistence allows us to ask queries of Omega without regard as to whether the data are stored live in memory or offline in a database. PowerLoom caches its results internally so that following similar queries can reuse prior inferences.

The following Common-Lisp API is provided to access Omega's objects directly. The previous SENSOR knowledge representation is also provided for backward compatibility, so the new API can also access objects stored in SENSOR format in-core. (However, not all components in Omega3 are delivered in SENSOR format, due to the impracticality of dealing with extremely large data sets using SENSOR). One can globally or dynamically select whether queries should be directed at the SENSOR or PowerLoom Omega knowledge bases.

• Lex(?lexeme,?concept,?part-of-speech,?frequency)
• Parents(?concept),Children(?concept), Siblings(?concept)
• Ancestors(?concept), Descendants(?concept)
• Definition(?concept)
• Relation(?relation-name,?concept) # includes attributes
• Words(?concept)
• Matches(?substring,?namespace, ?space-type, ?case-insensitive)
  [space-type can be "concept", "sense" or a known language ("EN","ES", etc.), indicating a lexical item]
• Word-senses(?word), Concept-senses(?concept)
• Sense-words(?sense), Sense-concept(?sense)
• Is-concept(?name,?namespace),
• Is-sense(?name,?namespace),
• Is-word(?name,?namespace,?language),
• Is-namespace(?namespace)