I know for certain projections the answers between 4.5 and 4.6 are different. I ran into that issue myself. So I suspect your problem is the difference in PROJ and not PostGIS.
I think you many need to change the proj4text in 4.6 to make it agree with old by adding an extra parameter. I forget what that is. I think the old 4.5 made an assumption of what that paramter is when its not present and 4.6 doesn't. Thanks, Regina -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Stefan Zweig Sent: Thursday, September 18, 2008 7:45 AM To: [email protected] Subject: [postgis-users] problems with transformation hi list, im a using two different installations of postgis. the first (1.) is for testing the second (2.) for working. (1.) select postgis_full_version() "POSTGIS="1.3.3" GEOS="3.0.0-CAPI-1.4.1" PROJ="Rel. 4.6.0, 21 Dec 2007" USE_STATS" (2.) select postgis_full_version() "POSTGIS="1.2.1" GEOS="2.2.3-CAPI-1.1.1" PROJ="Rel. 4.5.0, 22 Oct 2006" USE_STATS" i am running the same query on both installations, getting different results: (1.) select st_y (transform(setsrid(makepoint(-626172.139189,7514065.62361),9805), 4326)); 55.7765729937296 (2.) select st_y (transform(setsrid(makepoint(-626172.139189,7514065.62361),9805), 4326)); 55.9549116318344 the content for the srids 4326 and 9805 is equal on both installations: (1.) + (2.) select * from spatial_ref_sys where srid = 4326 or srid = 9805 srid;auth_name;auth_srid;srtext;proj4text 4326;EPSG;4326;GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]];+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs 9805;EPSG;9805; ;+proj=merc +lat_ts=0 +lon_0=0 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +units=m +no_defs actually i would suppose to get same results on both installations using transform() if the srid entries on both installations are equal. is there another point than the spatial_ref_sys table where the coordinate systems information can be set? to me it seems like installation (1.) calculates the transformation using a spheroid and (2.) using the wgs84 ellipsoid. any advices? thanks in advance + regards. stefan ________________________________________________________________________ Schon gehört? Bei WEB.DE gibt' s viele kostenlose Spiele: http://games.entertainment.web.de/de/entertainment/games/free/index.html _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users ----------------------------------------- The substance of this message, including any attachments, may be confidential, legally privileged and/or exempt from disclosure pursuant to Massachusetts law. It is intended solely for the addressee. If you received this in error, please contact the sender and delete the material from any computer. _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
