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    Re: UTM to lat/lon formulas
    From: Vic Fraenckel
    Date: 2003 Dec 12, 09:10 -0500

    George Huxtable wrote:
    | However, I'm a chap who prefers to do his own coding, if possible
    The open source code on my web site contains the conversion functions you
    are seeking. I completely understand your desire to "roll your own". I got
    the UTM conversion stuff from a very interesting manual "Map Projections - A
    Working Manual" which is the U.S. Geological Survey Professional Paper 1395
    written by John P. Snyder. Anyone interested in map projections needs to
    have this book. Everything you need is laid out there. Grab the source code
    from my site to use as somwhat of a reference and get the book and do your
    If I  can be of any help please let me know.
    Victor Fraenckel - The Windman
    vfraenc1 ATSIGN nycap DOT rr DOTcom
          Home of the WindReader Electronic Theodolite
                                   Read the WIND
    "Victory at all costs, victory in spite of all terror, victory however long
    and hard the road may be; for without victory there is no survival."
    - Winston [Leonard Spencer] Churchill (1874 - 1965)
    Dost thou not know, my son, with how little wisdom the world is governed?
    -Count Oxenstierna (ca 1620) to the young King Gustavus Adolphus
    ----- Original Message -----
    From: "George Huxtable" 
    Sent: Friday, December 12, 2003 7:56 AM
    Subject: Re: UTM to lat/lon formulas
    | I had asked for conversion algorithms between lat/long and UTM.
    | Paul Hirose is always reliable, and I was interested in his message-
    | >The "Explanatory Supplement to the Astronomical Almanac" also has the
    | >formulas, in a different format as I recall. Several years ago I tried
    | >to code up a routine based on that book, but never got it to work.
    | >Later someone told me the book had a misprint.
    | Especially as I had that volume (Siedelmann) on my shelves. It has the
    | conversion formulae that were exactly what I was looking for. I have coded
    | up one part of the conversion (lat/long to UTM but not yet vice versa) in
    | Basic on a pocket calculator, ready to test. I have taken heed of Paul's
    | warning about a misprint. If he can recall anything about that misprint,
    | in what way the problem showed up, it would be good to learn more.
    | Vic Fraenckel said-
    | >download GeoCalc from www.windreader.com/geodesy and be done with it.
    | Well, good advice perhaps, but is a version available that will run on my
    | old Mac?
    | than accept what others have done. In that way, you get to learn more
    | what's going on inside, and get the freedom to tinker and modify, which I
    | often enjoy. Of course, that then opens the question "well, how do you
    | the original algoriths are correct?", which is relevant particularly to
    | present case, in which Paul suspects a misprint. I might need to follow
    | that up in the original papers that Seidelmann refers to.
    | George.
    | ================================================================
    | contact George Huxtable by email at george---.u-net.com, by phone at
    | 01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    | Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    | ================================================================

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