Re: I've implemented the changes to xsd:dateTimeStamp

Hello Boris,
By my read, the situation regarding the value space of the
dateTime/dateTimeStamp is that there is a single value space, but that some
values are incomparable.

"Values from any one date/time datatype using the seven-component model (all
except duration <http://www.w3.org/TR/xmlschema11-2/#duration>) are ordered
the same as their
*·timeOnTimeline·*<http://www.w3.org/TR/xmlschema11-2/#vp-dt-timeOnTimeline>
values,
except that if one value's
*·timezoneOffset·*<http://www.w3.org/TR/xmlschema11-2/#vp-dt-timezone>
 is *absent* and the other's is not, and using maximum and minimum *·
timezoneOffset·* <http://www.w3.org/TR/xmlschema11-2/#vp-dt-timezone> values
for the one whose
*·timezoneOffset·*<http://www.w3.org/TR/xmlschema11-2/#vp-dt-timezone>
is
actually *absent*changes the resulting (strict) inequality, the original two
values are incomparable."


Is that your understanding?

-Alan

http://www.w3.org/TR/xmlschema11-2/#theSevenPropertyModel

On Sat, Mar 28, 2009 at 11:15 AM, Boris Motik
<boris.motik@comlab.ox.ac.uk>wrote:

> Hello,
>
> I have just implemented the change to the semantics of xsd:dateTimeStamp.
> While
> doing so, I took the liberty to clean up the datatype section a bit. The
> main
> problem was that the section was written as if it were defining various
> datatypes; for example, it said "The facets of xsd:string are
> such-and-such".
> This is clearly wrong: the facets of xsd:string are as defined in the XML
> Schema
> document, and there is nothing we can do to change this. Another problem
> was
> with the tables with the semantics of facets which were superfluous.
>
> To clarify all this, I have explicitly stated now that the sections defines
> only
> owl:real and owl:rational, and that the specification merely reuses the
> definitions of various datatypes. Hence, I've removed any attempts to
> (re)define
> XML Schema datatypes and have just added a bunch of examples by means of
> which
> we discuss certain consequences of their definition.
>
> I have also added an example in the section for functional data properties
> where
> we now discuss the difference between equality and identify.
>
> The diff showing the changes in the Syntax document is here:
>
> http://www.w3.org/2007/OWL/wiki/index.php?title=Syntax&diff=20865&oldid=20838
>
> No other document was changed in relation to this.
>
>
> Finally, I would just like to point out that we should include xsd:dateTime
> into
> our datatype map now. There is no good technical reason not to do so;
> furthermore, most of the ontologies out there use xsd:dateTime rather than
> xsd:dateTimeStamp so, according to our current solution, such ontologies
> are not
> OWL 2 ontologies. I hope we can discuss and resolve this at the next
> teleconf.
>
> Regards,
>
>        Boris
>
>
>