[Cfp-interest 2069] Re: Underflow

[Fred J. Tydeman]

On Tue, 20 Jul 2021 12:41:18 -0700 Jim Thomas wrote:
>
>The result underflows if a nonzero result with ordinary accuracy would have magnitude (absolute value) too small for representation as a normalized number in an object of the specified type. Also, the result may underflow if it (with ordinary accuracy) can be represented as a minimum-magnitude number in an object of the specified type and it is inexact 249).
>

That is getting better.

Would (min subnormal)*(0.49), which rounds to zero, be an underflow?
Would adding something like this be needed:  An exact zero is not an underflow

Also, may need words about "unless specified otherwise"
For example:  nextafter( min subnormal, zero) is zero with underflow and inexact.


---
Fred J. Tydeman        Tydeman Consulting
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