If you change the 180 to 179 do the results match up again? (ie, do any distance less than a perfect half-sphere?)
P On Thu, Apr 22, 2010 at 8:06 AM, Olivier Courtin <[email protected]> wrote: > > On Apr 22, 2010, at 4:49 PM, Paul Ramsey wrote: > >> They don't, at least for me: >> >> postgis14=# select st_distance_spheroid(geomfromtext('POINT(0 0)',4326), >> postgis14(# geomfromtext('POINT(180 0)',4326),'SPHEROID["WGS >> postgis14'# 84",6378137,298.257223563]'); >> st_distance_spheroid >> ---------------------- >> 20037508.3427892 > > > On this request i got as result: 19903593.3909346 > on two systems: > > POSTGIS="2.0.0SVN" GEOS="3.2.0-CAPI-1.6.0" PROJ="Rel. 4.7.1, 23 September > 2009" LIBXML="2.7.6" > PosgreSQL 9.0.alpha 4 > Mac OS X 10.5.8 > > POSTGIS="1.5.0SVN" GEOS="3.2.0-CAPI-1.6.0" PROJ="Rel. 4.6.1, 21 August 2008" > LIBXML="2.7.3" > PostgreSQL 8.3.7 > Linux Slackware 12.1 > > > -- > Olivier > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
