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    Re: Lat/Lon by "Noon Sun" & The Noon Fix PROVE IT
    From: Fred Hebard
    Date: 2009 Apr 23, 18:07 -0400

    Hewitt,
    
    I believe the AppleWorks program contains a spreadsheet.
    
    Fred
    
    On Apr 23, 2009, at 5:59 PM, Hewitt Schlereth wrote:
    
    >
    > George, I have a Mac iBook and it doesn't have a spread-sheet program.
    > Pressing F9 does absolutely nothing.
    >
    > The AppleWorks program did open your "long around noon.xls"
    > attachment. What I was presented with  looked much like a ledger page.
    >
    > The altitudes I used for figuring longitude were from the "perturbed
    > alt" row on that page. They were nearly equal - i.e.,10.812 at 1210,
    > 10.815 at 1250.
    >
    > The altitude for latitude was from the same "perturbed alt" row -
    > 10.914 at 1230.
    >
    > Hewitt
    >
    > On 4/23/09, George Huxtable  wrote:
    >> Hewitt Schlereth wrote-
    >>
    >>
    >>  | George, it looks like I may have misunderstood the document I
    >> got the
    >>  | (nearly) equal AM/PM altitudes from. I thought it was your
    >> spreadsheet
    >>  | and cited it's designation - LONG AROUND NOON.XLS (SS) - in the
    >>  | worksheet I attached to my e-mail. The numbers I used were from
    >> that
    >>  | document - which I took to be yours. They looked mighty like
    >> sextant
    >>  | altitudes; so, certainly not random numbers generated by me.
    >>  |
    >>  | Maybe my worksheet didn't come through to the List?  Here it is
    >> again.
    >>
    >>  ==================
    >>
    >>
    >> Hewitt and I have got ourselves at cross-purposes, it seems.
    >>
    >>  I had produced 20 simulated sets of "perturbed" sextant
    >> altitudes, each of
    >>  13 observations taken at regular intervals around noon. These
    >> were offered
    >>  so that list-members could analyse them in any way they chose, to
    >> try to
    >>  discover the original latitudes and longitudes on which they were
    >> based,
    >>  information which I withheld. The table was attached to [7940] as
    >>
    >> noon1a.rtf, or (the same data), attached to [7959], as noon1a.doc .
    >>
    >>
    >> In case anyone wanted to see how that data had been generated, I
    >> also added
    >>  the Excel spreadsheet, that generated those data sets.. Each time
    >> that
    >>  spreadsheet is run, (or when button F9 is pressed), a new set of
    >> random
    >>  numbers is generated, which creates a new, unique set of perturbed
    >>  altitudes. I hadn't intended anyone to use that spreadsheet
    >> itself to
    >>  generate those sets of altitudes, but there's nothing wrong with
    >> doing so;
    >>  indeed, that's what Dave Walden did, generating 1000 such sets to
    >> look for
    >>  the scatter.
    >>
    >>  Hewitt has done the same, but has generated only one such data-
    >> set, which
    >>  has given an answer which Hewitt tells is is within 1' of the
    >> intial value.
    >>  To which I suggest that if that is the case, it's only so as the
    >> result of a
    >>  fluke, and will not be repeatable.
    >>
    >>  If Hewitt will kindly load and run that Excel program again, it
    >> will invent,
    >>  this time, a completely new set of 13 altitudes, showing a
    >> similar general
    >>  shape but differing in every detail. And if he analyses the new
    >> set as he
    >>  did before, he will, I suggest, get a very different answer.
    >> Every time he
    >>  presses F9, it will change again.
    >>
    >>  However, having satisfied himself on that score, he could
    >> usefully apply
    >>  whatever technique he chooses, to one or more of the data sets
    >> attached to
    >>  those messages cited above, also attached here. The first two
    >> sets, only,
    >>  provide that original data. For the other 18, only I know the
    >> original lat
    >>  and long from which the data set has been constructed.
    >>
    >>
    >>  George.
    >>
    >>  contact George Huxtable, at  george{at}hux.me.uk
    >>  or at +44 1865 820222 (from UK, 01865 820222)
    >>  or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    >>
    >>>
    >>
    >>
    >
    > >
    
    
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