>Hello,
>
>Does anyone know how to calculate the distance between 2 coordinates ?
>
>More details :
>I have the coordinates (longitude + lattitude) of customer X and I have the coordinates of customer Y.
>I have to calculate the distance between the coordinates (bird's-eye view or how do you say that :o)
>
>Any ideas ?


This is from FoxPro 2.x developer's guide as is:

Function GeoDist
parameters lat1,lng1,lat2,lng2
*
* Degrees to radian
*
x = sin(lat1) * sin(lat2) +;
    cos(lat1) * cos(lat2) * cos(lng2 - lng1)
return 3959 * acos(x)

However this is distance for "as the crown flies" - thanks Terry for the idiom. I'm sure you could get exact distances from activex like MapInfo, MapObjects ... North America has quite well data. Expedia Maps might have some web services.
PS: GeoDist result is in miles.
Cetin