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Subject: Re: Computing tables
From: Tony (anthonys@XXX.XXX)
Date: Wed Sep 08 1999 - 19:20:56 EDT
Rick:
You ask the $64,000 question! Much depends on the data base used (as pointed
out by Gordon Talge in the just previous message) and the accuracy expected.
When implemented on a pc even to its maximum precision of 15-16 places, none
will coincide exactly with that of the Nautical Almanac. What can be expected
from more limited calculators is problematical. I'll venture the opinion that
all methods are within practicable limits. Understanding the bases and limits
of each is entwined.
Tony (author of Navig94 and its successors)
"Richard B. Emerson" wrote:
>
> In recent posts, some people referred to computing their own tables.
> Aside from the issue of selecting the correct equations, the question
> of computational accuracy comes to mind. I'm thinking of issues such
> as rounding error and the occasional FPU that has subtle but
> detectable algorithm errors. What checks are made to verify that the
> resulting tables are computationally sound?
>
> Rick
> S/V One With The Wind, Baba 35
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