Re: AW: How to represent geographic coordinates for maps

Hello Lars,

On 12-7-2013 15:55, Svensson, Lars wrote:
> My main point is that I cannot attach geo:hasGeometry (or wgs84) directly to the map but have to say that the map has a spatial extent (or describes something) that is a geo:Geometry.
I think that is correct. But is it a problem? The map can have a 
property 'spatial extent' and that property can be expressed as a geometry.
an example using GeoSPARQL and and the spatial coverage property from 
Dublin Core (http://dublincore.org/documents/dcmi-terms/#terms-spatial):

my:resource a ex:map;
     dc:title "The Marauder's Map";
     dct:spatial my:extent.
my:extent a geosparql:Geometry;
     geosparql:asWKT "POLYGON((45.33 -13, 45.33 49, 45.58 49, 45.59 -13, 
45.33 -13))"^^geosparql:wktLiteral.

>
> So assuming that we can encode the coordinates in a fashion that is easy to parse, I'd like to come back to my question no 2: Are coordinates for maps of any use at all to this community?

In general, I think it is a good idea to publish everything you know in 
the web of data.  You do not have to make assumptions on how the data 
will be used. One consumer will be interested in one selection of data, 
another consumer will be interested in a different selection. By 
publishing all facts, the greatest number of consumers will be 
satisfied.  So yes, I think it is a good idea to publish the 
geographical extent of the maps.

In this case, it is not really hard to think of a use case: By 
publishing the spatial coverage of the map in machine readable 
coordinates, it is possible to find maps that have some kind of 
topological relationship with other geographical features (or other maps).


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