[Cfp-interest] Functions and infinity

[Jim Thomas]

> On Jun 20, 2018, at 10:48 AM, Fred J. Tydeman <tydeman at tybor.com> wrote:
> 
> On Wed, 20 Jun 2018 10:18:52 -0700 Jim Thomas wrote:
>> 
>>>>> remainder -
>>>>> 754: remainder(x,inf) for finite x;
>>>>> cfp: x not infinite
>>>>> => x=NaN is different.
>>>> 
>>>> Aren't NaN argument cases handled globally, in both 754 and cfp?
>>> 
>>> C and cfp do for Annex F, but not main body of standard.
>>> 754 does, but requires a canonical quiet NaN result.
>>> 
>>> The difference here for remainder is:  cfp requires that if x is a NaN,
>>> that same NaN be returned.
>> 
>> Hmm. Where does cfp say that?
> 
> 18661-1, F.10.7.2 (pdf page 41)
> 
> -        remainder(x, +/-inf)   returns x       for     x       not     infinite.

Right. We should change “not infinite” to “finite” to match 754. Editorial?

- Jim

> 
> 
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> Fred J. Tydeman        Tydeman Consulting
> tydeman at tybor.com      Testing, numerics, programming
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