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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@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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