I was under the impression that using srid 4326 meant that point coordinates would correspond to latitude and longitude on a spheroid such that st_distance(...) between two such points would give the angle between them, hence 90 in this case. As you say, st_distance is treating these points as cartesian coordinates, giving 127. I guess I've got the wrong idea somewhere.
Regards Nicholas Lan ________________________________ This e-mail communication contains confidential information that may also be privileged. It is intended for the exclusive use of the addressees. If you are not the person or organization to whom it is addressed, you must not copy, distribute or take any action based on the information contained within. If you have received this communication in error, please notify Ursa Minor B.V. immediately [telephone +31 (0) 15 2682559]. Ursa Minor B.V. will not accept liability for contractual commitments made by individuals employed by this company outside the scope of our business. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Chris Hermansen Sent: Wednesday, January 16, 2008 5:36 PM To: PostGIS Users Discussion Subject: Re: [postgis-users] degrees between points Nicholas: sqrt(90*90 + 90*90) is about equal to 127, as ST_DISTANCE() reports. Why are you expecting your distance to be 90? Nicholas Lan wrote: > > Hello, > > > > Im a newbie and have been trying to find the degrees between points > on a sphere. From reading the documentation I have a table with column > named 4326 of srid 4326. > > > > I insert into this column a point, Geomfromtext(POINT(0 0), 4326) > > > > And then doing > > > > select ST_DISTANCE("4326",Geomfromtext('POINT(90 90)', 4326)) as dist > from test3; > > > > I expected to see 90 but got 127. What am I doing wrong? Sorry if this > is a stupid question. > > > > Regards > > Nicholas Lan > > > > ------------------------------------------------------------------------ > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > -- Regards, Chris Hermansen · mailto:[EMAIL PROTECTED] tel:+1.604.714.2878 · fax:+1.604.733.0631 Timberline Natural Resource Group · http://www.timberline.ca 401 · 958 West 8th Avenue · Vancouver BC · Canada · V5Z 1E5 C'est ma façon de parler. _______________________________________________ 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
