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Re: [Axiom-developer] i-output and decimal width
From: |
Waldek Hebisch |
Subject: |
Re: [Axiom-developer] i-output and decimal width |
Date: |
Mon, 6 Aug 2007 21:56:26 +0200 (CEST) |
Stephen Wilson wrote:
> Stephen Wilson <address@hidden> writes:
> > Could I suggest the following to replace these two cases:
> >
> > (+ 1 |negative| (round (log n 10)))
>
>
> This should _not_ be used to replace both cases, but only the first.
> I believe the second case might be OK unless the `over estimation'
> is not enough account for the width in the negative case.
>
> However, these messages are now adrift a bit premature, so perhaps
> someone may know of a better solution?
>
I looked at this code and I belive that I have written a better
version (commited to wh-sandbox). Some remarks:
- Ansi says that for exact arguments results are either exact or
single precision. I feel that single precision give us no
help so I use double precision arguments (as type gcl does not
distingiush between single and double, but it stil gave only
single precision result).
- for moderate lengths if numerical result is suspect I use
extra verification.
- for large arguments I use over-estimate.
--
Waldek Hebisch
address@hidden