Mike wrote: > I've searched the mailing list archives, the web, read the FAQ, etc and I > don't see anything relevant so here it goes… > > I'm trying to implement a radius based searching based on zip/postal codes.
Here is a selection of interesting threads from the Lucene ML with relevant info: <http://www.nabble.com/all-records-within-distance----small-index-tf3303731.html> <http://www.nabble.com/Hacking-proximity-search%3A-looking-for-feedback-tf1201416.html> <http://www.nabble.com/Announcement%3A-Lucene-powering-Monster-job-search-index-%28Beta%29-tf2522646.html> The standard answer seems to be something like: 1. Index latitude and longitude fields with fixed length (left-zero-padded) integral values - shift the decimal point to the right to the desired level of discriminability. (In your case, convert the postal codes to lats/longs.) 2. Do a range query on both your lat and your long fields to collect hits inside a bounding box with your target at the center and with sides of length double the desired radius. 3. Optionally, sort (and filter) the results by distance from your target, displaying only those within the desired radius. If you leave out this step, you'll get some hits that are outside of the desired radius - inbetween the bounding circle and the bounding box. Steve -- Steve Rowe Center for Natural Language Processing http://www.cnlp.org/tech/lucene.asp --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
