Pol(Tan DEC Cos Lat - Sin Lat Cos LHA , -Sin LHA ) = r and Theta (see image)
North(+) South(-)
r is stored in answer key and the x variable
Theta is stored in the y variable
Arc Cos ANS Cos Dec = Hc (calculated altitude)
360 + theta = azimuth
See this link for a good explanation.
http://fer3.com/arc/m2.aspx/Sight-reduction-using-calculators-POL-arctan2-key-Bernecky-apr-2018-g41742
Alternate Pol formula using the Casio variables: A (assumed latitude), D (declination), and M (meridian angle LHA)
Pol(Tan D Cos A - Sin A Cos M , - Sin M) = r theta
Arc Cos Ans Cos D = Hc
360 + theta = azimuth
note- to store in variables: angle entered: degree (DMS) minutes tenths (DMS) Shift STO A,D,M
