A shortcut to programming Code in C of Ephemeris of the Sun (Height and Azumuth): http://aa.usno.navy.mil/software/novas/novas_info.html (Site currently not accessible, pleas use next line below).

Excerpt files: Readme.txt (NOVAS-C) and solsys3.c (please click to open).

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Astronomy and numerical software source codes are found at http://www.moshier.net/index

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http://www.redrok.com/analemma.htm - at the bottom of this page Duane C. Johnson provides a zipped listing (file “sun.zip”) of Sun-Ephemeris together with Refraction calculation code. Authors are Stephen Moshier and Keith Burnett. Thanks to all.                                *****