## code for great circle?

wonder if anyone have stumbled across ready code for this - i.e., the code to get from phi1 theta1 to phi2 theta2 on sphere.
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 "Code"? In what language? All you should really need to do is just copy equation (5) from that page, it should work almost verbatim as code in almost any programming language, just remember that $$cos^{-1}$$ becomes for example "acos" in C.
 for starters, eq. 5 gives nothing but distance. what I need is deltas of phi and theta (ideally as a function of t = 0....1). the language could be anything that remotely looks like c (i.e. not lisp). the reason to ask for code is to avoid making bugs that were already made and fixed. so far, closest to what I am looking for is greatcircle.py, but I'm open for other options :)