Re: Table 4 proposal version 0.2...
On 2012-03-17 18:16:37 -0400, Michel Hack wrote:
> (I should note in passing that AIX long double arithmetic is not
> directly usable for interval arithmetic because it does not support
> directed rounding -- only round-to-nearest. I actually broke that
> rule in my recent support of new radix conversions for AIX, which do
> honour all four rounding directions -- but that nice property goes
> away as soon as arithmetic is performed on the long double results.)
Supporting only round-to-nearest is OK for mid-rad. The implementation
just needs to provide certified error bounds. Note that valid inf-sup
(but not tightest) can also be implemented if you have these error
bounds.
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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