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Re: On behalf of Jim Demmel -- Re: back to the roots

Am 01.07.2013 21:10, schrieb Vincent Lefevre:

On 2013-07-01 13:39:02 -0500, Ralph Baker Kearfott wrote:

Please see the following communication from Jim.

My point is that the precision needs to be controlled by the user.
Sometimes small precision datums are sufficient, sometimes one needs
more accuracy. P1788 doesn't specify how precision is controlled
(and I think it shouldn't, because there are many possibilities each
one with its own advantages), but it doesn't forbid that. Ensuring
exactness is in general not possible (even if you have EDP with
fixed-precision inputs, as the result can't be reused as an input).
But the rouned result of the EDP is of high accuaracy. It does not suffer from cancellation. 

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