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Lat/Lon data source for addresses

Hi Experts, I have been given an assignment of taking a list of addresses and determining the lat/lon for them. I'm at a bit of a loss as to how this can be accomplished. I did see a previously entered note here which did the job in HTML for a single address. I didn't understand how it was accomplished. The best solution for me would most likely be an Access DB solution (I have 2010 installed on my PC but I think that the work would most likely be done in Access Basic (I'm familiar with Access 2007 Basic, not 2010 if there's any difference)).

Anyone have an idea as to how I can do this automatically instead of just typing in addesses manually into Google Maps and cutting and pasting the lat/lons into the list?

Rich

PS For this process, let's assume the list of addresses I have will be in tab delimited format. I can work with Acess Basic, Office VBA and I'm rusty in VB6. I also have access to SQL Server but am just learning that now. My strength is Access.

RCUllrich

You need to purchase a database or subscribe to a service to get the Latitude and Longitude for an address. In the past my client purchased a database that had the Latitude and longitude for every ZIP code in the US. However, that used a single value for each ZIP code (If I remember correctly it was the geographical center of the ZIP code.)

If you had an API for Google Maps or some other online service, then you could query that service with an address and get the Latitude and longitude.

The Google Maps APIs give developers several ways of embedding Google Maps into web pages, and allows for either simple use or extensive customization. There are now several API offerings:
•Google Maps Javascript API
•Google Maps API for Flash
•Google Static Maps API

If you operate an enterprise or commercial website, you may also be interested in Google Maps API for Business. (this option requires payment of a fee)

ifpugnacious

This process is called "geocoding." If ZIP/Postal Code center isn't enough, e.g. you're really trying to locate the "house" or other structure, you will need to use a 3rd party service as RCUllrich describes above. Or you will need access to a Geographic Information System (GIS). I was involved with this exact problem for a previous client and we were using ESRI's ArcGIS.

Particularly if you have old (road names changed), new construction, or rural addresses, a significant number will fail to geocode, or you will get back a latitude and longitude but they won't be very accurate. Most of these systems work by interpolation of the number between road endpoints like intersections.

There doesn't appear to be a Geographic Information Systems (GIS) Zone here. But "GIS" and "geocoding" are the magic words.

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redmondb

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RichNH

ASKER

This looks like the cat's meow. I do note something interesting in the app. I have had several people tell me that their GPS units have taken them to the next driveway south of us instead of our drive. When I used this app on my home address, it took me to the driveway south of me instead of my house, maybe a 50 yard error. But I think this may be close enough for our purposes. We will get a new Yahoo user ID for using this product. Thank you again.

redmondb

Thanks, RichNH. Glad to help.

Interesting that there's an apparently consistent error on your address. My guess, is that at some point, at least one organisation matched your address to slightly incorrect co-ordinates. I assume that the database in question was then used by a number of different companies - including Yahoo.

Of course, it's always possible that your neighbour is a lonely hacker. :)

RichNH

ASKER

LOLOLOL, Perhaps, he's married with a couple of small kids, but you can never tell... :-)

redmondb

They are his kids? =:0