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    Re: Floating-Point 4-place Nat-Haversine Table
    From: Tony Oz
    Date: 2018 Dec 10, 11:52 -0800

    Hello!

    I need Mathematician's help [again]. :)

    Doing the arcHaversine with the tabulated 4-places values I see that in the 90°±53° range (where no-gimmicks involved, just rounding) the difference between the "true" and calculated angle bounces between an ~arcsecond and ~twenty arcseconds.

    This difference quickly drops to the level of few arcseconds where the "characteristic" (denoted by my bar-n digit) reaches 1 and 2. Further on - the difference is sub-arcsecond.

    Do we need such unbalanced resolution in the table?

    May I reduce the number of significat digits at higher "characterictic"? For example, arcHaversine of bar-7,85 is spot on for the 0°2'. Looks like the highes meaninful value for the "characteristic" is 5. And we'd rather have 5-places mid-table keeping 4-places outside the 90°±53° range.

    Please comment.

    Warm regards,

    Tony

    60°N 30°E

       
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