Re: Motion 31: V04.2 Revision of proposed Level 1 text
On 2012-01-25 11:07:04 -0800, Dmitry Nadezhin wrote:
> 2) fma(x,y,z)
> The operation fma is mentioned in definitions, but the document
> don't clarify the status of interval version fma. Is it required,
> recommended or none ?
At Level 1, it is the same as x * y + z. I wonder whether it should
be defined. Level 2 could introduce a generic concept of fused
operations, and recommend or require some of them.
(If there is a dot product, why not a sum of n intervals?)
> 3) negate(x) = -x
> The unary minus is an operator in most programming languages.
> Shouldn't we require interval version of negate ?
This is equivalent to 0 - x, and since { 0 } can be exactly
represented by [0,0], negate(x) may not be really necessary.
Ditto for recip(x), since { 1 } can also be exactly represented
by [1,1].
Well, at least I assume this is true for implicit types.
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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