Re: Motion M0050:EDP-Without-CA
On 2013-10-01 11:14:14 +0300, Svetoslav Markov wrote:
> I would gladly change my vote if someone answers my contra-argumnts
> of sept 16. I slightly modify my first argument to make it more clear.
>
> To the agument of Richard Fateman:
>
> I think that translation from end-point (EP) to mid-rad (MR)
> form and vice versa will benefit from the EDP. In particular,
> if one of the two forms (say EP) is a numeric resul of
> some computation (degenerate interval),
> obtained as EDP-data object, then the other form (say MR)
> may be necessarily nondegenerate interval. The latter will
> be (or may be) sharper if EDP is available.
>
> Thus, translation actually may involve intervals. This means that
> EDP is not related just to numbers, and its use is justified in an
> interval standard.
This translation is done by the implementation, either by EDP
or directly in a *more efficient way*. You don't need EDP in
the external interface for that.
> To the agument of Vincent Lefevre:
>
> If EDP is available then the operations exact sum or an exact product
> of two numbers are readily available as special cases of EDP.
This is an ugly way to get them, and it may be difficult (if not
impossible, e.g. in case of a library) for the compiler to detect
these special cases and optimize.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)