geo-indexing: efficiently calculating proximity based on latitude/longitude

Posted by AnC on Stack Overflow See other posts from Stack Overflow or by AnC
Published on 2010-03-17T07:48:41Z Indexed on 2010/03/17 7:51 UTC
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geolocation

My simple web app (WSGI, Python) supports text queries to find items in the database. Now I'd like to extend this to allow for queries like "find all items within 1 mile of {lat,long}".

Of course that's a complex job if efficiency is a concern, so I'm thinking of a dedicated external module that does indexing for geo-coordinates - sort of like Lucene would for text.

I assume a generic component like this already exists, but haven't been able to find anything so far. Any help would be greatly appreciated.

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