I do (using MySQL): where = '( 6378.137 * acos( cos( radians(%s) ) * cos( radians( `events_locations`.`latitude` ) ) * cos( radians( `events_locations`.`longitude` ) - radians(%s) ) + sin( radians(%s) ) * sin( radians( `events_locations`.`latitude` ) ) ) ) < %s' % (lat, lng, lat, dist) basic = basic.exclude(location__latitude=0).extra(where=[where])
The exclude was needed for some select_related stuff I do. You may can leave it out... >reply to message: >date: 11.08.2011 17:09:09 >from: "Thomas Weholt" <thomas.weh...@gmail.com> >to: django-users@googlegroups.com >subject: [<django-users.googlegroups.com>] "Great circle" using the django ORM? > >I got a model with longitude and latitude and want to be able to find >other objects nearby a selected object. Can this be done using the >django orm? What is the best approach to do this in a django project? > >I found a answer on Stackoverflow, but doesn't work with sqlite. Doing >it in SQL is ok and probably the best solution performance wise, but >if it has to be done in python I'll do that too. > >Ref question on stackoverflow: >http://stackoverflow.com/questions/4610717/django-determining-if-geographic-coordinates-are-inside-of-an-circle > >-- >Mvh/Best regards, >Thomas Weholt >http://www.weholt.org > >-- >You received this message because you are subscribed to the Google Groups >"Django users" group. >To post to this group, send email to django-users@googlegroups.com. >To unsubscribe from this group, send email to >django-users+unsubscr...@googlegroups.com. >For more options, visit this group at >http://groups.google.com/group/django-users?hl=en. > -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
