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Re: Motion M0050:EDP-Without-CA



On 2013-10-01 12:54:21 +0300, Svetoslav Markov wrote:
> Sorry, I do not understand what you say.  If a true numeric result is a
>  number (degenerate interval) like 12345 + 12345^(-50) 

You probably meant 12345 + 12345*10^(-50).

> then the MR form can be a tight number if an
> EDP-data object is available, and a wider interval if not available.
>  In particular, if a true numeric result is the number  
> 1 + 1^(-50) then the MR form will be an exact number if an
> EDP-data object is available, and will be an interval if not available.

This is confusing. A mid-rad representation is different than a
degenerate (singleton) interval like [12345 + 12345*10^(-50)].
If it's a degenerate interval of the form [x+y], you shouldn't
call it mid-rad.

While that's true that an EDP-data object can represent such a
value exactly, you *don't need* such an object. P1788 already
allows interval types with whatever precision you like and
whatever representation you like, with greater benefit than
EDP-data objects: the operations on an EDP-data objects are
rather limited, while you have all the P1788 operations on
interval types.

Moreover many applications don't need such a form specifically.
So, the representation of such forms should be left to the
implementation, just like it is the implementation that chooses
the precision of interval types.

-- 
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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