[postgis-tickets] [PostGIS] #2534: st_distance is returning incorrect results for large geographies

[PostGIS]

#2534: st_distance is returning incorrect results for large geographies
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 Reporter:  samuelb                 |       Owner:  pramsey      
     Type:  defect                  |      Status:  new          
 Priority:  medium                  |   Milestone:  PostGIS 2.1.1
Component:  postgis                 |     Version:  2.0.x        
 Keywords:  st_distance, geography  |  
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 Following geography distance query:

 SELECT st_distance(st_geographyfromtext('POINT(-0 0)'),
 st_geographyfromtext('POLYGON((-20 -20,-20 60,90 60,90 -20,-20 -20))'))

 returns 2226389.81558413 instead of the expected result 0 as you get for
 the same query but with geometries:

 SELECT st_distance(st_geomfromewkt('SRID=4326;POINT(-0 0)'),
 st_geomfromewkt('SRID=4326;POLYGON((-20 -20,-20 60,90 60,90 -20,-20
 -20))'))

 I've tried adding extra vertices to my rectangle but that didn't help.

 When you slightly decrease to a maximum latitude of 55 then it works:

 SELECT st_distance(st_geographyfromtext('POINT(-0 0)'),
 st_geographyfromtext('POLYGON((-20 -20,-20 55,90 55,90 -20,-20 -20))'))

 Changing the order of the coordinates didn't work. In the end I would like
 to be able to check if a point is within 2km of the bounding box (-179
 -85) (179 85) as this is one of the geometries in my database.

 Note that st_dwithin also returns false instead of true.

 Tested on
 "PostgreSQL 9.1.10 on x86_64-unknown-linux-gnu, compiled by gcc
 (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, 64-bit POSTGIS="1.5.3"
 GEOS="3.2.2-CAPI-1.6.2" PROJ="Rel. 4.7.1, 23 September 2009"
 LIBXML="2.7.8" USE_STATS"

 and on:

 "PostgreSQL 9.2.4, compiled by Visual C++ build 1600, 32-bit
 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 GDAL_DATA not found"
 LIBXML="2.7.8" LIBJSON="UNKNOWN" RASTER"

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/2534>
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