Looking For Geodetic Python Software

[Diez B. Roggisch]

> For spherical earth, this is easy, just treat the 2 locations as
> vectors whose origin is at the center of the earth and whose length is
> the radius of the earth.  Convert the lat-long to 3-D rectangular
> coordinates and now the angle between the vectors is 
> arccos(x dotproduct y).  The over-ground distance is then just R*theta
> where theta is the angle.

It's a bit more complicated in the real world - usually one takes a 
spheroid as defined by the wgs84 standard:

http://www.codeguru.com/Cpp/Cpp/algorithms/article.php/c5115/

Maybe for python, this is enteresting (haven't used it myself though):

http://pyogclib.sourceforge.net/


Diez