Also... There are some possibilities when asking the "get all the zip codes within 40 miles of a given zip" question.
Do you want distance from the center (centroid) of the Zip Code to centers of other Zip Codes? Do you want distance from the edge of the Zip Code to edges (touching) other Zip Codes? Do you want only Zip Codes that are completely encompassed (contains) by the radius? Each of these possibilities can result in drastically different answers. Also, every Zip Code polygon by definition is different as there is no such thing as an area defined by a USPS Zip Code, at least not officially. Every company that produces a database does it by guessing and approximations so they are always different. Due to this, your answer using any of the listed methods will differ depending on the database as well. Bottom line: No matter how you approach this problem, there is no exact answer, only approximations. Try using this program as an example: http://maps.huge.info/zipcolors.htm -John Coryat http://maps.huge.info http://www.usnaviguide.com http://www.zipmaps.net -- You received this message because you are subscribed to the Google Groups "Google Maps API V2" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-maps-api?hl=en.
