The template creation script referenced [here] (http://docs.djangoproject.com/en/dev/ref/contrib/gis/install/#ubuntudebian) doesn't work on Ubuntu Lucid, where the default PostgreSQL version is now 8.4 and some things have been moved around. I've edited the script to work on Ubuntu Lucid.
this is an enhancement to paulsmith's code snippet 190, to provide an extra "search by distance" parameter rather than "limit number of results returned". i need this for a social networking site where users can search for people within a certain geographical area.
This code assumes a) that you are using PostgreSQL with PostGIS and b) that the geometry column in your model's table is populated with points, no other type of geometry. It also returns a list instead of a QuerySet, because it was simpler to sort by distance from the given point and return that distance as part of the payload than to muck around with QuerySet. So bear in mind that any additional filtering, excluding, &c., is outside the scope of this code. 'Distance' is in the units of whatever spatial reference system you define, however if you do not intervene degrees decimal is used by default (SRID 4326, to be exact). To get distance in units a little easier to work with, use a spatial ref close to your domain set: in my case, SRID 26971 defines a projection centered around Illinois, in meters. YMMV.
3 snippets posted so far.