Comments on: Java, GPS Receivers, and Geocaching: Vincenty’s Formula http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/ Mike Gavaghan blogs on Java, C#, .Net, and the software industry Thu, 20 Nov 2008 23:00:40 +0000 http://wordpress.org/?v=2.1.3 By: Javier http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-76 Javier Mon, 26 Nov 2007 11:31:39 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-76 Fantastic article about the application of Vincenty's formula. It can be very useful. Fantastic article about the application of Vincenty’s formula. It can be very useful.

]]> By: paul http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-208 paul Mon, 17 Nov 2008 17:05:48 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-208 Hi, Yours is the only c# implementation of Vincenty's direct formula that I've come across on the net and I've a little problem that you might be able to help me with. Before I found this implementation I recoded the NGS downloadable fortan into c# myself and while both my and your implementations both work to give the same results, I'm finding them wrong and am wondering if you might know what the problem could be. I'm a PhD student in Ireland, Europe and if I enter the following simple values into either my or your implementation I get the same results to 10 decimal places, these are wrong though. However, if I enter these values into the NGS online calculator I get the correct results - http://www.ngs.noaa.gov/cgi-bin/Inv_Fwd/forward2.prl . Our implementations are producing an incorrect Longitude and I can't seem to isolate the problem. Values: Latitude: 53.387125N Longitude: 6.58569W Azimuth: 218.512579 Distance: 59.352571 Any help you might be able to offer would be greatly appreciated. Thanks in advance. Paul Hi,
Yours is the only c# implementation of Vincenty’s direct formula that I’ve come across on the net and I’ve a little problem that you might be able to help me with. Before I found this implementation I recoded the NGS downloadable fortan into c# myself and while both my and your implementations both work to give the same results, I’m finding them wrong and am wondering if you might know what the problem could be. I’m a PhD student in Ireland, Europe and if I enter the following simple values into either my or your implementation I get the same results to 10 decimal places, these are wrong though. However, if I enter these values into the NGS online calculator I get the correct results - http://www.ngs.noaa.gov/cgi-bin/Inv_Fwd/forward2.prl . Our implementations are producing an incorrect Longitude and I can’t seem to isolate the problem.
Values:
Latitude: 53.387125N
Longitude: 6.58569W
Azimuth: 218.512579
Distance: 59.352571

Any help you might be able to offer would be greatly appreciated.
Thanks in advance.

Paul

]]> By: Paul http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-209 Paul Tue, 18 Nov 2008 14:32:51 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-209 My complete apologies, there is nothing wrong with either your or my code implementation. I'm just a brainless idiot who has spent far too long looking for a big problem when a minus sign should have been obvious. Sorry. Paul My complete apologies, there is nothing wrong with either your or my code implementation. I’m just a brainless idiot who has spent far too long looking for a big problem when a minus sign should have been obvious. Sorry.

Paul

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