Re: Accuracy of 754-compliant recommended functions
On 2013-07-01 09:53:23 -0500, Ralph Baker Kearfott wrote:
> Does this mean that, if the functions recommended in 754-2008 are
> provided, they must return the nearest floating point number
> subject to the rounding mode in effect?
Yes. But whar you had said wasn't clear.
> That is what I originally
> thought it said. The relevant sections of 754-2008 are
> Clause 9.1, in which it says "A conforming
> function shall return results correctly rounded for the applicable rounding
> direction for all operands
> in its domain. The preferred quantum is language-defined," and
> the definition of quantum: "2.1.44 quantum: The quantum of a finite
> floating-point representation is the value of a
> unit in the last position of its significand. This is equal to the radix
> raised to the exponent q, which
> is used when the significand is regarded as an integer."
>
> Where do you get that a quantum is defined only for decimal?
I think that what Michel meant was that there may be different choices
for the quantum only in decimal (where the representation isn't
necessarily normalized, contrary to binary).
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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