No it is not meters. What you can do is casting to geography type on the fly, something like:
select o.osm_id, ST_AsText(ST_Transform(o.way,4326)), ST_Length(ST_Transform(o.way,4326)::geography) The you will get your answer in meters. I think that cast will work, but I havenot tried. HTH Nicklas On Thu, 2012-03-22 at 11:32 +0100, Ed Linde wrote: > Hi All, > Am trying to measure the length of road segments from OSM (open street map) > and getting some weird values. Is this in meters? If so its too small. > Is my query right? > > > select o.osm_id, ST_AsText(ST_Transform(o.way,4326)), > ST_Length(ST_Transform(o.way,4326)) > from planet_osm_line o > where o.highway is not null; > > > 26781954;"LINESTRING(12.4488377563054 55.7052298677097,12.4475093276633 > 55.7050849548856,12.4459445522699 55.7049392822841,12.444526741257 > 55.7048546522258,12.4432355926991 55.7048141593102,12.4415570905907 > 55.7047361597132,12.439932936557 55.7046743571964,12.4383072553874 > 55.7046393812816,12.4376592107414 55.704619792731)";0.0112000095550213 > > 26487076;"LINESTRING(12.4376603785513 55.7323555892184,12.4377151757836 > 55.7341099847101,12.4377174215718 55.734184081729,12.4377245182625 > 55.7344121883925,12.4377250572517 55.7344266536481)";0.00207207442718709 > > 114383319;"LINESTRING(12.4378901676009 55.7615479714339,12.4377832680821 > 55.7617575712814,12.4376867890206 55.7619467509818)";0.000447647154409751 > > > cheers, > Ed > _______________________________________________ > 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
