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    Re: Which calculator to use for "arctan(tan(269))"?
    From: Tony Oz
    Date: 2016 Nov 4, 08:48 -0700

    Yo!, Robert!

    :)

    Zc = Pol{ [ cos(LatAP) · tan(Dec) - sin(LatAP) · cos(LHA) ] , [-sin(LHA) ] }

    the θ value should be in the correct quadrant.

    It works!!!

    Huge thanks! :)

    Just one question: how did you come up with those operands for the Pol() function? I'd like to be able to use this trick on any relevant occasion. I ask because these operands do not look like just parts of the formula I used from the SR work-sheet:

    Zc = atan{ [ cos(Dec) · sin(GHA + LonEP) ] / [ cos(LatEP) · sin(Dec) - sin(LatEP) · cos(Dec) · cos(GHA + LonEP) ] }

    Your explanation is most welcome!

    Warmest regards,

    Tony

       
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