[Cfp-interest] Functions and infinity

[Fred J. Tydeman]

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.       


---
Fred J. Tydeman        Tydeman Consulting
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