Why OWL Unit Ontology has no Log/Exp (Was: Re: OWL ontology for unit)

[Brian Thomas]

On Tuesday 02 September 2003 03:48 am, David Berry wrote:
>
> Once you have analysed the unit string into its basic SI units and the
> relationships between them, it is surely possible to use this analysis to
> work out the transformation between them - without the need for any
> further ontologes. The Starlink AST library for manipulating WCS
> information (http://axp0.ast.man.ac.uk/~dsb/ast/ast.html) does this.
>

	I agree. In fact in the original draft that Ed showed to me we discussed
	whether or not the mathematical functions should be included. I believe
	the last thought was that, no, these should be separate, and perhaps
	belong in another schema/ontology or library. The log and exp functions
	were seen as being part of said "other half". WCS probably is a good point 
	to start looking for requirements on this set of mathematical functions
	needed for full unit represenation.

	The beauty of having OWL, IMO, is that it should bridge over to UML, and thence
	actual code fairly easily, with the bonus that you are deriving all of the code and
	fundemental functionality from the ontology. In that sense, you can have 
	mathematical ontologies work (eg. just have to transform them into something else).	


				-b.t.