Question

I have a database of US based street addresses for which a client of mine offers their services. I am working on a form that would allow a customer to enter in their zip code or address to see if there is service in their area.

Is there a component or an algorithm “out there” somewhere that I can use as a template?

I have played with GIS and the tiger zips in a previous geolocation project but am not sure this is the best way to go.

Answer 1

Here is one crude approach:

1. First, the client’s service
   territory needs to be geographically
   referenced as areal units or
   polygons on a map.
2. Second, get the geographic
   coordinates of the zip-code polygons
   (you can parse the shapefile).
3. Third, loop over and find the service
   polygons that overlap the chosen zip-code polygon
   by performing an overlapping polygon
   test. You can use the python
   shapely library.

Of course, you can speed things up by some how adding information on the centroid proximity structure or contiguity structure of the polygons so there was less looping needed.

good luck