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    Re: Degrees and minutes vs decimal degrees and the Daily Pages
    From: Tom Sult
    Date: 2015 Oct 17, 11:23 -0500
    The key is the word equivalent. A min is 1/60 of a degree. And a decimal is 1/10. So you need to use D.XX in decimal to get similar equivalency.

    Also since many programs use a . As the delineator between D.m. You need to know what you are using. The conversion back and forth will seldom  be exactly the same due to rounding issues.  

    Tom Sult, MD
    Author: JUST BE WELL

    On Oct 17, 2015, at 06:57, Steve E. Bryant <NoReply_Bryant@fer3.com> wrote:

    Dear Navlisters,

    My question(s) have to do with calculating things like sun rise, sun set, meridian transits and any other calculation that requires the manipulation of degrees and minutes of GHA or LHA.

    Is it more or less accurate to strictly use either degrees and minutes (D,m) as opposed to the use of decimal degrees (D.0) and converting back to D,m when entering the Daily Pages?

    There are some in our Power Squadron JN class who insist that all calculations must not be converted to decimal equivalents.  I am not sure if that requirement is made because those who grade the work prefer seeing the problems worked like that or if there is some potential for a (slightly) different result.  Intuitively, it seems that there could be no real issue given the fact that computers use a binary system in order to perform these same routine calculations.  So, if one choses to use the decimal equivalent, is there a limit to the number of decimal places that should be used?

    Best regards,


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