Thanks all for the suggestions. Mark, I am well aware that there is an infinite number of points on the circle at distance X from a known location. To start with, for my application, my plan is to find 16-64 of the locations at distance X from my location. That should be sufficient.
The problem I have is that, unless I am mistaken, all GC formulas are of the form d = some formula using lat/lng of two locations. In my case, I know d and lat/lng of one location. I need to find lat/lng of the second location. In order to solve this kind of equation (two unknowns), I could use some form of estimation or some other approach. Unless I am missing something obvious, I think I may need to figure something out using the geometry of a circle combined with some type of estimation. Thanks. Alex Donnini On Aug 22, 7:04 am, "Thomas (geomancer)" <[email protected]> wrote: > I had the same problem and found my sources > athttp://williams.best.vwh.net/avform.htm > . Ed Williams goes into detail on great circle navigation. I took his > formulas for distance between points and true course and translated > them into PHP. Projecting a point is given as well. The translated > PHP formulas calculate the same numbers as my Garmin 76cxs. > Regards, Tom Birchmire > > On Aug 22, 4:17 am, Panut Sunyakorn <[email protected]> wrote: > > > This will help you. > > >http://www.movable-type.co.uk/scripts/latlong.html > > > 2009/8/22 Mark Murphy <[email protected]>: > > > > alexdonnini wrote: > > >> I had already considered using the GCC formula (I did not know the > > >> name GCC). Unfortunately, the only lat/lng information I have is mine, > > >> none other. This is why the problem is a little trickier. > > > > There are an infinite number of latitude/longitude combinations at a > > > distance X from a fixed point. You are going to need some other > > > criteria, such as a direction, in order to come up with your second > > > position. > > > > -- > > > Mark Murphy (a Commons Guy) > > >http://commonsware.com|http://twitter.com/commonsguy > > > > Android Training in Germany, 18-22 January 2010:http://bignerdranch.com > > > -- > > > Panut Sunyakorn > > 086-334-1616 > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
