Hi Rob I've created a new entry in /usr/share/proj/epsg, calling it 27701 for now presumably units are abbreviated to 'dm' ??
Not sure what you meant by this bit however then use +init=my: thanks chris Robert Coup-4 wrote: > > On Tue, Jul 20, 2010 at 8:06 AM, chrispg <chrisember...@hotmail.com> > wrote: > >> >> I have data in British Nat Grid that I would like to load into postgis. >> Normally I would use EPSG:27700 to do this no problem, but the >> coordinates >> are to decimetre precision, not metre, so 27700 is out by a factor of 10. >> I >> can edit the spatial_ref_sys.sql to generate a custom projection file, >> but >> then performing any queries on that using the PROJ4 libraries are a >> problem >> as it is not recognised. Has anybody come across this before? >> > > Maybe add your new projection to the proj4 library as well? > > Copy the 27700 line from /usr/share/proj/epsg to /usr/share/proj/my using > a > new number (eg. 927700), set the same number in spatial_ref_sys, and then > use +init=my:927700 with proj4, and srid=927700 in postgis... > > If decimeters are regularly used in datasets, consider submitting to > http://www.epsg.org/ to get assigned an "official" number. > > Rob :) > > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users > > -- View this message in context: http://old.nabble.com/custom-EPSG-codes--tp29200110p29216323.html Sent from the PostGIS - User mailing list archive at Nabble.com. _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
