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move example to ST_HausdorffDistance

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git-svn-id: http://svn.osgeo.org/postgis/trunk@11608 b70326c6-7e19-0410-871a-916f4a2858ee
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Regina Obe 2013-07-02 16:11:55 +00:00
parent c7adb0717b
commit e7a5fb010b
1 changed files with 7 additions and 6 deletions
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13
doc/reference_measure.xml
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@ -2098,8 +2098,13 @@ The current implementation supports only vertices as the discrete locations. Thi
<refsection>
<title>Examples</title>
<para>For each building, find the parcel that best represents it. First we require the parcel intersect with the geometry.
DISTINCT ON guarantees we get each building listed only once, the ORDER BY .. ST_HausdorffDistance gives us a preference of parcel that is most similar to the building.</para>
<programlisting>SELECT DISTINCT ON(buildings.gid) buildings.gid, parcels.parcel_id
FROM buildings INNER JOIN parcels ON ST_Intersects(buildings.geom,parcels.geom)
ORDER BY buildings.gid, ST_HausdorffDistance(buildings.geom, parcels.geom);</programlisting>
<programlisting>postgis=# SELECT st_HausdorffDistance(
<programlisting>postgis=# SELECT ST_HausdorffDistance(
'LINESTRING (0 0, 2 0)'::geometry,
'MULTIPOINT (0 1, 1 0, 2 1)'::geometry);
st_hausdorffdistance
@ -2149,11 +2154,7 @@ The current implementation supports only vertices as the discrete locations. Thi
</refsection>
<refsection>
<title>Examples</title>
<!-- <para>For each building, find the parcel that best covers it. First we prefer the parcel first that completely covers.
Then for those that only partially cover we prefer the parcel whose furthest part from the building closer than any other parcel.</para>
<programlisting>SELECT DISTINCT ON(buildings.gid) buildings.gid, parcels.parcel_id
FROM buildings INNER JOIN parcels ON ST_Intersects(buildings.geom,parcels.geom)
ORDER BY buildings.gid, ST_MaxDistance(buildings.geom, parcels.geom);</programlisting> -->
<para>Basic furthest distance the point is to any part of the line</para>
<programlisting>postgis=# SELECT ST_MaxDistance('POINT(0 0)'::geometry, 'LINESTRING ( 2 0, 0 2 )'::geometry);
st_maxdistance