On Wed, Mar 14, 2012 at 07:58:37PM -0400, Stephen Woodbridge wrote: > You might want to look at the book: "PostGIS In Action" pg 225 has a > function to cut a linestring at point junctions. > > Basically, you want to take your two points and construction a line like: > > select astext(setsrid(makeline(pnt1, pnt2), 4326)); > > then get a collection of pieces of myline after we subtract your new > line from it: > > select astext(st_difference(myline, setsrid(makeline(pnt1, pnt2), 4326)));
In 2.0 there's also ST_Split for that purpose. For the cut-line-by-line case it should be faster than st_difference. Semantic is slightly different in that you get a collection out of ST_Split, not a multiline. --strk; ,------o-. | __/ | Delivering high quality PostGIS 2.0 ! | / 2.0 | http://strk.keybit.net - http://vizzuality.com `-o------' _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
