Re: [R-sig-Geo] LL from bearing and distance

2007-09-27 Thread Eric Archer
All, I have ported JavaScript code from a couple of websites to R for three functions that solve my problem. 'calc.destination.sphere' assumes a perfect spheroid with a given radius 'calc.destination.ellipsoid' assumes an ellipsoid 'calc.destination.Vincenty' uses the Vincenty model which app

Re: [R-sig-Geo] LL from bearing and distance

2007-09-27 Thread Arien Lam
The following function does what Eric describes, if the earth's surface is close enough to a sphere. Roger, I'll try to document it properly for inclusion in Maptools. Cheers, Arien # compute the place where you end up, if you travel # a certain distance along a great circle, # which is uniqu

Re: [R-sig-Geo] LL from bearing and distance

2007-09-27 Thread Roger Bivand
On Thu, 27 Sep 2007, Eric Archer wrote: > Is there a package that contains a function that will allow me to calculate > the ending latitude and longitude given a starting point on the earth's > surface and bearing and distance? I have searched the archives but have been > unable to find one an

[R-sig-Geo] LL from bearing and distance

2007-09-27 Thread Eric Archer
Is there a package that contains a function that will allow me to calculate the ending latitude and longitude given a starting point on the earth's surface and bearing and distance? I have searched the archives but have been unable to find one and would like to double check before I try to rol