[postgis-tickets] [PostGIS] #2168: ST_Distance is not always commutative

[PostGIS]

#2168: ST_Distance is not always commutative
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 Reporter:  realityexists  |       Owner:  pramsey      
     Type:  defect         |      Status:  new          
 Priority:  medium         |   Milestone:  PostGIS 2.0.4
Component:  postgis        |     Version:  trunk        
 Keywords:                 |  
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Changes (by jkania):

 * cc: jkania (added)


Comment:

 I get 0 for that query but for this one:
 {{{
 SELECT ST_Distance('POINT(18.5107234 54.7587757)'::geography,
 'POINT(18.58218 54.7344227)'::geography)
         - ST_Distance('POINT(18.58218 54.7344227)'::geography,
 'POINT(18.5107234 54.7587757)'::geography);
 }}}
 I get 1.18234311230481e-010.

 {{{
 "POSTGIS="2.0.3 r11132" GEOS="3.3.8-CAPI-1.7.8" PROJ="Rel. 4.8.0, 6 March
 2012" GDAL="GDAL 1.9.2, released 2012/10/08" LIBXML="2.7.8"
 LIBJSON="UNKNOWN" RASTER"
 }}}
 {{{
 "PostgreSQL 9.2.3, compiled by Visual C++ build 1600, 32-bit"
 }}}
 Windows 7 32-bit.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/2168#comment:8>
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