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    Re: Z tangent formula
    From: John Simmonds
    Date: 2005 Jul 7, 19:46 +1000
    Actually, I would suggest that the Sharp nav calculator uses the same formula, truncated to 1 decimal place :)

    John
    live every day like it may be your last .. cause one day it will be

    >snip<
    >
    >?I've taken 3 sights at random to contrast a few different (?)
    >?methods of azimuth determination. The first comes from the problem
    >?Mike Burkes posed, that I worked out and posted here on the 2 July.
    >
    >?Sun UL Azimuth - in decimal form, and to 3 decimal places if
    >?available 101 ? ? ? ? ? ? 'Bennett book' azimuth tables 100.9
    >? ? ?Sharp nav. calculator 100.982 NavPac 100.985 ? ? ? ? Z tan
    >?formula
    >
    >?The other two come from the first other worked sights to hand.
    >?Details available if anyone's interested.
    >
    >?Miaplacidus Azimuth
    >?183 ? ? ? ? ? ? 'Bennett book' azimuth tables
    >?182.6 ? ? ? ? ? Sharp nav. calculator
    >?182.637 NavPac
    >?182.665 Z tan formula
    >
    >?Dubhe Azimuth
    >?010 ? ? ? ? ? ? 'Bennett book' azimuth tables
    >?010.2 ? ? ? ? ? Sharp nav. calculator
    >?010.238 NavPac
    >?010.214 Z tan formula
    >
    >?So I'm convinced, pending further tests, that the Z tan formula is
    >?a valid and accurate method for determination of azimuth. The small
    >?differences seem insignificant. It is not significantly more
    >?tedious or time consuming to calculate, given a good scientific
    >?calculator, than the other methods. This is because the calculator
    >?and NavPac require quite a lot of data to be entered to give a
    >?result.
    >
    >?However, I do wonder whether one method or another does give a more
    >?precisely accurate result, although the answer is probably
    >?irrelevant for most practical purposes. Am hampered, admittedly, by
    >?not knowing what methods my calculator or NavPac use. Anyone have
    >?other formulas for comparison purposes? Or ideas on this?

       
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