[Cfp-interest 1302] Re: isnoralized()

[Fred J. Tydeman]

On Sun, 28 Apr 2019 15:23:14 -0400 Stephen Canon wrote:
>
>Ah, misread the list name as IEEE instead of CFP. So, yes, adding the macro would get you somewhere for S/360 and double-double. But it's still not clear to me what the utility of this operation is.
>
>> On Apr 28, 2019, at 3:22 PM, Stephen Canon <scanon at apple.com> wrote:
>> 
>> I don't get it. The S/360 hex format and double-double aren't IEEE 754 formats, so adding an isnormalized( ) classification macro to IEEE 754 isn't going to do anything for them.
>> 
>> For decimal, I think you mean "cohort" rather than "quantum"-what you've written doesn't make sense otherwise.
>

For S/360 hex unnormals and DFP cohorts (thanks for the correction), you know that the 
number has less than full precision. One can get full precision by normalizing the number.

For double-double, you know that the number has low precision that will go away once the
number is normalized.  So, that "extra" precision cannot be counted on if more operations
are done using that number.

But, as far as real utility, I do not know.


---
Fred J. Tydeman        Tydeman Consulting
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