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    Re: from a watcher
    From: Dave Weilacher
    Date: 2002 Oct 17, 20:11 -0700

    >    cos(c) = cos(a)*cos(b) +
    > sin(a)*sin(b)*cos(ab)
    Isn't this the flatlanders side-angle-side trig formula.
    I had thought there was a 'we live on a ball' complication.
    Asking because I truly don't know answer.
    As for the sight reduction tables in the back of the nautical almanac.  Since
    it basically splits the nav triangle into two pieces, you have to make two
    passes through the tables to get an answer.  Because I tend to blunder at
    every other step, I'd much rather carry the standard tables.  That cuts my
    blunders in half immediately.  Besides it takes longer to reduce a sight with
    them.  The guy is already out on a boat, loving to sail, hating arithmetic,
    and soaked to the skin, if I've pictured it right.
    Dave Weilacher
    .US Coast Guard licensed captain
    .    #889968
    .ASA certified sailing and celestial
    .    navigation instructor #990800
    .IBM AS400 RPG contract programmer

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