Here is an example of getting all the zipcodes within a certain radius -
Something I did in SAS but I am sure you can convert the formula into another language. http://www.sconsig.com/sastips/tip00156.htm Chuck Patridge Charles Patridge Full Capture Solutions, Inc. 333 Roberts Street, Suite 400 East Hartford, CT 06108 Phone: 860-291-9517 x 106 Email: [EMAIL PROTECTED] -----Original Message----- From: Steven Rowe [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 29, 2007 12:37 PM To: [email protected] Subject: Re: Postal Code Radius Search 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-tf3303 731.html> <http://www.nabble.com/Hacking-proximity-search%3A-looking-for-feedback- tf1201416.html> <http://www.nabble.com/Announcement%3A-Lucene-powering-Monster-job-searc h-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] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
