here is the data

https://github.com/apache/jena/blob/master/jena-spatial/src/test/resources/geoarq-data-1.ttl

and here are the tests

https://github.com/apache/jena/blob/master/jena-spatial/src/main/java/examples/JenaSpatialExample1.java




On Mon, May 29, 2017 at 5:34 PM, Nouwt, B. (Barry) <[email protected]> wrote:
> Hi Marco,
>
>
>
> Ok, so, I will not need to implement any spatial predicates myself? Which
> existing spatial predicate should I use in my SPARQL query for my ‘contains’
> requirement?
>
>
>
> Could you maybe send me your quick test? That would probably be helpful.
>
>
>
> Thanks again!
>
> Barry
>
>
>
> Verzonden vanaf mijn Windows 10-telefoon
>
>
>
> Van: Marco Neumann
> Verzonden: maandag 29 mei 2017 23:12
>
>
> Aan: [email protected]
> Onderwerp: Re: FW: Apache Jena Spatial
>
>
>
> looking at your requirements it I'd say you will be just fine with the
> current version of jena-spatial. I was thinking more in terms of
> number of spatial objects to be indexed as a possible issue.
>
> I just did a quick test with the latest release 3.3.0 and and it seems
> to work for your needs. ignore the spatial documentation for now and
> work with code directly. the linked documentation seems to be out of
> sync with the current implementation of jena-spatial.
>
> Marco
>
>
> On Mon, May 29, 2017 at 1:24 PM, Nouwt, B. (Barry) <[email protected]>
> wrote:
>> Hi Marco, thanks for your reply!
>>
>>
>>
>> I’ve indeed included the JTS library, but haven’t tested the more advanced
>> (WKT) features yet…
>>
>>
>>
>> My (current) requirements are:
>>
>> Describe spatial objects in RDF using WKT polygons.
>> Fire a spatial SPARQL query with a given GPS coordinate (I.e. single
>> point)
>> Retrieve all spatial RDF objects that contain this given GPS coordinate.
>>
>>
>>
>> Do I understand you correctly that the current spatial implementation does
>> not support my requirements? So, there is no predefined (combination of)
>> predicate like nearby that I can use?
>>
>>
>>
>> So, then I need to put more effort in it myself. I’ve seen the ‘simple’
>> implementations of the nearby (etc) predicate in jena-spatial… would
>> implementing the contains be similar? I am an experienced Java developer,
>> but never did spatial calculations before.
>>
>>
>>
>> Regards, Barry
>>
>>
>>
>>
>>
>>
>>
>> Verzonden vanaf mijn Windows 10-telefoon
>>
>>
>>
>> Van: Marco Neumann
>> Verzonden: maandag 29 mei 2017 18:39
>> Aan: [email protected]
>> Onderwerp: Re: FW: Apache Jena Spatial
>>
>>
>>
>> Barry,
>>
>> the jena-spatial implementation has seen a couple of versions and
>> iterations of versions over last couple of years.
>>
>> To perform and test for detailed spatial object interactions on polygons
>> the current apache lucene spatial implementation (Lucene6.4.1) requires
>> the
>> JTS library.
>>
>> and of course you can always implement your own or you can just build your
>> own spatial filter in sparql to detect polygon / point intersections. it
>> requires a bit more effort to detect polygon / polygon interactions
>> though.
>> it depends on your requirements.
>>
>> Marco
>>
>>
>>
>> On Mon, May 29, 2017 at 11:28 AM, Nouwt, B. (Barry) <[email protected]>
>> wrote:
>>
>>> Hi,
>>>
>>>
>>>
>>> In one of our projects we would like to use SPARQL to do spatial searches
>>> to find all spatial objects (described by a polygon) that contain a
>>> particular given GPS coordinate. I can successfully execute the following
>>> Apache
>>> Jena Spatial query on the test data:
>>>
>>>
>>>
>>> PREFIX spatial: <http://jena.apache.org/spatial#
>>> <http://jena.apache.org/spatial>>
>>>
>>> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#
>>> <http://www.w3.org/2000/01/rdf-schema>>
>>>
>>>
>>>
>>> SELECT ?placeName
>>>
>>> {
>>>
>>>     ?place spatial:nearby (51.46 2.6 *1000* 'km') .
>>>
>>>     ?place rdfs:label ?placeName
>>>
>>> }
>>>
>>>
>>>
>>> However, the *‘nearby’* predicate does not fit my usecase and I cannot
>>> find one that does in this list:
>>>
>>>
>>>
>>> https://jena.apache.org/documentation/query/spatial-
>>> query.html#property-function-library
>>>
>>>
>>>
>>> I think I need the ‘Contains’ predicate as described here:
>>>
>>>
>>>
>>> http://edndoc.esri.com/arcsde/9.1/general_topics/understand_
>>> spatial_relations.htm#Contains
>>>
>>>
>>>
>>> but I it seems like it is not supported. Can anyone confirm that?
>>>
>>>
>>>
>>> What other options do I have to get the usecase described above working?
>>> Can I implement the ‘Contains’ behavior myself (although I have no
>>> geo/spatial experience) and contribute it to the Apache Jena Spatial? Can
>>> I
>>> somehow mimic the contains behavior with regular SPARQL?
>>>
>>>
>>>
>>> Thanks in advance!
>>>
>>>
>>>
>>>
>>>
>>> B. (Barry) Nouwt
>>> Medior Innovator Semantische Technologie
>>> Connected Business
>>>
>>> T +31 (0)88 866 56 91
>>> M +31 (0)64 977 53 56
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>>>
>>>
>>>
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>>>
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>>>
>>>
>>
>>
>>
>> --
>>
>>
>> ---
>> Marco Neumann
>> KONA
>>
>>
>>
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>
>
>
> --
>
>
> ---
> Marco Neumann
> KONA
>
>
>
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