python - Getting near objects. Django + Badoo -


i have following situation.

i keep track of user's longitude , latitude using ios. send longitude , latitude coordinates django server.

how can use these longitude , latitude coordinates determine objects near?

basically how can use these coordinates determine list of other users near user?

assuming backend object has lat , longitude, here's useful snippet making proximity query:

objects = objectmodel.objects.exclude(lat__isnull=true).exclude(lng__isnull=true).extra(               where=["3956 * 2 * asin(sqrt(power(sin((%(lat)s - abs(lat)) * pi()/180 / 2), 2) + cos(%(lat)s * pi()/180 ) * cos(abs(lat) * pi()/180) * power(sin((%(lng)s - lng) * pi()/180 / 2), 2) )) < 50" % {'lat': lat, 'lng': lng}],           )

similar question: determine longitudes , latitudes within range


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