install(namespace('geom2d'));
install(namespace('geo'));


setHomeAndTopic(resource("http://www.mapbureau.com/rdfmapper/2.0/examples/ex1"));

geom2d:Point function extractGeoLatLong(Resource x)
{
   var geom2d:Point rs;
   if  ((count(x,geo:lat)>0) && (count(x,geo:long)>0))
	   {
	   rs = new(geom2d:Point);
	   rs . geom2d:x = x.geo:long;
	   rs . geom2d:y = x.geo:lat;
	   return rs;
	   }
   return nil ~  geom2d:Point;
}


geom2d:Point function extractTopicLocation(Resource itm)
{
   if  (count(itm,foaf:topic)>0) 
	   return extractGeoLatLong(itm.foaf:topic);
   return nil ~ geom2d:Point;
}