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    Re: Haversines with Logarithms
    From: Matthew Gianelloni
    Date: 2020 Oct 11, 04:46 -0700

    Thanks, Frank. Quick Sunday Morning answer: Logs were of course, done on Excel. I adjusted the log base value to produce 99.999999999 as the result for 0°01'. Then the other 10,799 results followed. This was to accommodate a planned "wallet card" with the values for everyday carry. (Whole degrees, of course, to be interpolated in a lifeboat situation.) I was playing around with it. Any log base will do. Natural logs work fine. I've attached a spreadsheet with the first row. The point of having the logs is to allow the final calculation on the meridian angle algorithm to be a subtraction instead of a division. Dividing one 9-decimal-place number by another is too tedious on paper. 

    I'm no mathematician. But I am good at simplifying things. This whole thing started as a "wallet card cel nav" idea, to dispense with H.O. 229 in an emergency and then evolved as it went. 

    I just want the stuff out there. No desire for credit or return. I have gotten way more from this forum than from Kings Point. Granted, that was 1986. 

    I'll stay tuned. Questions welcome.

    Matt

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    Log-Base-for-All-Haversines.xlsx
       
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