Algorithm to find all Latitude Longitude locations within a certain distance from a given Lat Lng location

Question

Given a database of places with Latitude + Longitude locations, such as 40.8120390, -73.4889650, how would I find all locations within a given distance of a specific locatio

Answer 1

As biziclop mentioned, some sort of metric space tree would probably be your best option. I have experience using kd-trees and quad trees to do these sorts of range queries and they're amazingly fast; they're also not that hard to write. I'd suggest looking into one of these structures, as they also let you answer other interesting questions like "what's the closest point in my data set to this other point?"