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    Re: Exercise #5 Lat/Long near Noon.
    From: Andrés Ruiz
    Date: 2008 Jun 2, 10:58 +0200

    Less than one minute with the “Polynomial LS” software: Copy the t/Hs to a file. Open it and push the [Fit] bottom.

     

    Usually, when I go sailing, I go alone, or I am the only who know to do it. I don’t have time to leave the cockpit, so I take sights and use my software to do the calculations quickly.

    Andrés

     


    De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de Anabasis75@aol.com
    Enviado el: lunes, 02 de junio de 2008 10:41
    Para: NavList@fer3.com
    Asunto: [NavList 5245] Re: Exercise #5 Lat/Long near Noon.

     

    Wow Andres,

     

    Way too much Calculus for me to handle out here at sea.  I have been removed from this math for more then a decade.  Interesting to see the errors in each sight from the graphs however.  Good to determine my personal error in sights.  I see you have me off of LAN by 5 seconds if I am reading this correctly.  I will have to recompute Hs to Ho for your time to determine Lat error when I am next on the bridge.  I will post those results (unless anyone beats me to it).

     

    I am definitely going to repeat this experiment in the Fall when I return out here to see how the results change when the sun is in the Southern declinations and closer to the Equinox.  I hope that you run the data and see how we do.  I just hope I can give you a good set of data.

     

    Jeremy

     

    In a message dated 6/2/2008 6:25:52 P.M. West Pacific Standard Time, aruiz@orona.es writes:

    Jeremy,

    I have attached the Hs and time of LAN using Least squares fitting:
    The curve equation is: Hs = a0+a1*t+a2*t2
    The maximum gives:
    t LAN =     -a1/(2a2)
    Hs LAN =     a0-a2t2

    Andrés
    <BR


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