Mileage between 2 zipcodes / cities

[Newbie09]

Hello,
I'm new to iPhone dev and Obj C. I am looking for a way to find the distance between 2 cities/zips. Calculating the distance based on Longitude/Latitude does not seem right. Is there any other MAP API that is available in Iphone SDK?

I do not want to display MapView in my App. I just need to find the distance

Thanks

[smasher]

Originally Posted by Newbie09

Hello,
I'm new to iPhone dev and Obj C. I am looking for a way to find the distance between 2 cities/zips. Calculating the distance based on Longitude/Latitude does not seem right. Is there any other MAP API that is available in Iphone SDK?

I do not want to display MapView in my App. I just need to find the distance

Thanks

There is nothing in the SDK to convert a city or a zip to latitude/longitude, or to calculate distance between cities, zips, or locations.

You'll need your own database of cities or zip codes (eitehr online or stored in the app) to turn a city/zip into a lat/long. To get the distance between two nearby locations, you'll have to convert from lat/long to miles and then use the Pythagorean theorem - sqrt(dx*dx + dy*dy). You must convert to miles or km before you get the distance, because the number of miles in a degree differs based on location.

For points that are far apart (for example, LA to New York) you'll need to figure the great circle distance to account for the curve of the earth.

[Newbie09]

Originally Posted by smasher

There is nothing in the SDK to convert a city or a zip to latitude/longitude, or to calculate distance between cities, zips, or locations.

You'll need your own database of cities or zip codes (eitehr online or stored in the app) to turn a city/zip into a lat/long. To get the distance between two nearby locations, you'll have to convert from lat/long to miles and then use the Pythagorean theorem - sqrt(dx*dx + dy*dy). You must convert to miles or km before you get the distance, because the number of miles in a degree differs based on location.

For points that are far apart (for example, LA to New York) you'll need to figure the great circle distance to account for the curve of the earth.

Thanks Smasher. Why would Apple expect the developers to have their own database that has this information. If there are 10 apps in an iPhone that needs to calculate distance between 2 places, there will be 9 redundant instances of this DB (which is like 500k). I found this link interesting. This has information about how to obtain the DB

Perseverance Trumps Talent / Calculate the distance between two U.S. zip codes

[WeatherMan]

I doubt very many apps on the app store needs zip to Long/Lat.

Also, they change quarterly (new zips, etc) so Apple would have to send down updates to every iphone.

500K is not that much.