Is it possible for us to add ObjectUnionOf and DataHasValue to ELK?

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Mar 8, 2013, 1:57:21 PM3/8/13
We are developing a special tools using ontology but run into issues with performance. Elk is super fast and meet our needs. But we need ObjectUnionOf and DataHasValue. I am wondering whether it is possible to extend Elk to support those. If so, how difficult? Greatly appreciated if additional instruction is provided. 

Best regards,

Yevgeny Kazakov

Mar 8, 2013, 4:59:57 PM3/8/13
ObjectUnionOf is not in the OWL EL profile [1], so it is unlikely that
this feature will be added to ELK any time soon.
You can try to use the ConDOR reasoner [2], which supports
ObjectUnionOf (not sure about DataHasValue). But ConDOR is in a very
preliminary state, in particular it works only from the command line.

Alternatively, you can use MORe [3] which combines ELK with HermiT,
and can reason over more expressive ontologies than ELK with some
graceful performance degradation (depending on how many features you
have not in the OWL EL profile).

It would also be useful if you could share with us your ontology, so
that we can add it to our benchmark suit and this way let other
reasoners be optimized for that.

Best regards,



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Olexandr Pospishniy

Mar 9, 2013, 12:06:53 PM3/9/13
There is an experimental (although stable) branch of ELK with extensive datatype support that you might find useful for your task:

You need to compile it from source though. This version handles DataHasValue and DataSomeValuesFrom expressions and supports wide range of XSD and OWL datatypes. Although always sound, reasoning might be incomplete for some cases. If you provide more information about your ontology I will try to help you with it.
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