Re: SPARQL-friendly alternative to rdf:Lists?

Hi David and everybody,
I have a related problem in a framework in which I use SPARQL
Construct queries to generate XML (in practice HTML+SVG)
visualizations (like in TopBraid SPARQL Web Pages).
Initially for the DOM I used an ontology with properties
firstChild/lastChild and previousSibling/nextSibling (similar to
collection-ontology properties firstItem/lastItem and
nextItem/previousItem).
But building SPARQL Construct queries to order items with an ontology
like these is quite contrived.
In the ontology (still unpublished) I'm using now the order of items
is defined in the "container" node using properties childrenOrderedBy
and childrenOrderType.
The usage is the following:

ex:containerElem1
  xml:childrenOrderedBy ex:property1 ;
  xml:childernOrderType xml:Ascending ;
  xml:hasChild ex:childElem1, ex:childElem2, ex:childElem3 .

ex:childElem1 ex:property1 ex:value1 .
ex:childElem2 ex:property1 ex:value2 .
ex:childElem3 ex:property1 ex:value3 .

The semantic interpretation is that the child elements are ordered by
the values (ex:value1,ex:value2,ex:value3) of the selected property
(ex:property1). The comparison is based on the semantics of the SPARQL
">" operator. The selected property should be functional.

This approach simplified my queries: I don't need to generate the
prev/next statements nor to mint the exact numeric indexes. Moreover,
a child element is independent form the container (e.g. it can be in
two different lists, even ordered by different properties).

Of course this is not a general solution to the "list representation
in RDF/OWL" problem but may be it has some use cases a part from my
specific one.
Let me know if any of you think it could be useful to generalize this
kind of approach.

Best,
Miguel


On Sat, Oct 12, 2013 at 7:13 PM, Paolo Ciccarese
<paolo.ciccarese@gmail.com> wrote:
> Dear David,
> I apologize I just realized I replied to you only. I resend my email to the
> group.
>
> We experimented with ordering many years ago because of the needs we had in
> several software projects.
>
> One of the needs was the representation of the ordering of authors of
> publications, but we had many others including representation of the flow of
> the scientific discourse in publications.
>
> The results are summarized in Collections Ontology (already mentioned by
> Micheal):
>
> The paper explain many of the principles and features:
> http://www.semantic-web-journal.net/content/collections-ontology-creating-and-handling-collections-owl-2-dl-frameworks-0
>
> Wiki/Ontology
> http://code.google.com/p/collections-ontology/w/list
>
> Best,
> Paolo
>
>
> On Sat, Oct 12, 2013 at 11:40 AM, Michael Brunnbauer <brunni@netestate.de>
> wrote:
>>
>>
>> Hello David,
>>
>> I use the Collections Ontology: http://purl.org/co
>>
>> rdf:Lists should also be avoided because they cannot be used with OWL.
>>
>> Regards,
>>
>> Michael Brunnbauer
>>
>> On Fri, Oct 11, 2013 at 10:02:29AM -0400, David Booth wrote:
>> > rdf:Lists are notoriously difficult to use in SPARQL if one wishes to
>> > retain the *order* of the items in the list.  James Leigh and David Wood
>> > made a nice proposal a few years ago to address this problem directly at
>> > the RDF level,
>> > http://www.w3.org/2009/12/rdf-ws/papers/ws14
>> > but for whatever reasons, that work was not included in the charter of
>> > the current RDF working group.  As a result people often use some other
>> > means of representing ordered lists in RDF, such as by [item, index]
>> > pairs.
>> >
>> > For those who use an alternate way to represent an *ordered* list of
>> > items in RDF (instead of rdf:List), I am wondering:
>> >
>> > 1. What *ordered* list representation do you prefer, and why?
>> >
>> > 2. Have there been any efforts toward standardizing alternative
>> > *ordered* list representations in RDF?  E.g., has anyone written up a
>> > spec on how they prefer to do it?
>> >
>> > Thanks,
>> > David
>>
>> --
>> ++  Michael Brunnbauer
>> ++  netEstate GmbH
>> ++  Geisenhausener Straße 11a
>> ++  81379 München
>> ++  Tel +49 89 32 19 77 80
>> ++  Fax +49 89 32 19 77 89
>> ++  E-Mail brunni@netestate.de
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>> ++
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>> ++  Prokurist: Dipl. Kfm. (Univ.) Markus Hendel
>
>
>
>
> --
> Dr. Paolo Ciccarese
> http://www.paolociccarese.info/
> Biomedical Informatics Research & Development
> Instructor of Neurology at Harvard Medical School
> Assistant in Neuroscience at Mass General Hospital
> Member of the MGH Biomedical Informatics Core
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>
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Received on Monday, 14 October 2013 08:56:56 UTC