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GeoSPARQL 是否提供计算两个线串之间距离的功能？（编辑：我正在使用带有 GeoSPARQL 扩展的 Jena Fuseki。）

结果没有按预期工作。

线串查询，假设所有几何图形也是线串：

prefix geo: <http://www.opengis.net/ont/geosparql#> 
prefix geof: <http://www.opengis.net/def/function/geosparql/> 
prefix ogis: <http://www.opengis.net/def/uom/OGC/1.0/>
select * where {
  ?s geo:hasGeometry ?f .
  ?f geo:asWKT ?wkt.
  BIND(geof:distance(?wkt,
    "<http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.8 -87.6,41.8 -87.5)"^^geo:wktLiteral,
    ogis:kilometre) as ?distance)
}
ORDER BY asc(abs(?distance))

相反，如果我计算点之间的距离，那么这将按预期工作。

点，假设所有的几何图形也是点：

prefix geo: <http://www.opengis.net/ont/geosparql#> 
prefix geof: <http://www.opengis.net/def/function/geosparql/> 
prefix ogis: <http://www.opengis.net/def/uom/OGC/1.0/>
select * where {
  ?s geo:hasGeometry ?f .
  ?f geo:asWKT ?wkt .
  BIND(geof:distance(?wkt,
    "<http://www.opengis.net/def/crs/EPSG/0/27700> POINT(41.8 -87.6)"^^geo:wktLiteral,
    ogis:kilometre) as ?distance)
}
ORDER BY asc(abs(?distance))

那么点到线的距离呢，反之亦然？

编辑：这是给定我的数据集的线对线搜索的结果。距离显然是错误的。这些线通常不超过几公里，但所有这些结果都显示为小于 1 公里。例如，最后一个结果显示为 0.35KM，但它在路易斯安那州，而原始点在伊利诺伊州。

同样，这些结果来自带有 GeoSPARQL 扩展的 Jena Fuseki。

select ?wkt ?distance where {
  ?s a sosa:featureOfInterest .
  ?s geo:hasGeometry ?f .
  ?f geo:asWKT ?wkt.
  BIND(geof:distance(?wkt,
    "<http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.85003 -87.65005,41.85 -87.65)"^^geo:wktLiteral,
    ogis:kilometre) as ?distance) .  
}
ORDER BY asc(abs(?distance))
limit 10
指数 wkt.value 距离值
0 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(46.7082 -89.9785,46.7 -89.9892) 0.168957e0
1 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(46.699902 -89.989067,46.669998 -90.046654) -0.186799e0
2 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.84 -87.607,41.839 -87.605) 0.205283e0
3 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.865 -87.607,41.863 -87.607) 0.208798e0
4 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(46.708 -89.978,46.7096 -89.9749) 0.246481e0
5 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.894 -87.614,41.894 -87.612) 0.26358e0
6 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.904 -87.624,41.902 -87.622) 0.272661e0
7 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.8234 -87.5966,41.8215 -87.595) 0.278589e0
8 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(41.924 -87.63,41.914 -87.62) 0.326035e0
9 <http://www.opengis.net/def/crs/EPSG/0/27700> LINESTRING(29.226625 -90.001852,29.211947 -90.026484) -0.353463e0
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