[Proj] Accurate algorithm for geodesic calculations
Gerald I. Evenden
geraldi.evenden at gmail.com
Sun Mar 1 10:52:47 EST 2009
On Saturday 28 February 2009 5:17:14 pm Charles Karney wrote:
> I've implemented an algorithm for geodesic calculations for an ellipsoid
> with the following features:
> * It uses expansions accurate to 8th order in the ellipsoid flattening.
> This gives 12 nm accuracy using doubles and 6 pm accuracy using long
Ahh! Nothing like overkilling a subject. ;-)
Given that all other work with the Earth misses by many order of magnitude the
need for such precision.
> The code itself (C++ classes and a program for doing geodesic
> calculations) is available at
Not to throw cold water on C++ which I can understand provides a useful
service in certain applications but I feel that C++ contributes little, if
anything, to small, limited application procedures. Certainly, for someone
with less than expert experience with C++, your code is nearly unreadable
based upon previous experience. In the TM code, C++ only obfuscated the
Again, this is not a language war, only a comment on how to reach the widest
audience. Anyone who is an expert in C++ can easily understand a C procedure
but the reverse in not true.
The whole religious complexion of the modern world is due
to the absence from Jerusalem of a lunatic asylum.
-- Havelock Ellis (1859-1939) British psychologist
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