[Cfp-interest 1828] Re: Preferred quantum exponent for exact result

[Jim Thomas]

5.2.4.2.3 #6 says “… When exact, these operations produce a result with their preferred quantum exponent, or as close to it as possible within the limitations of the type. When inexact, these operations produce a result with the least possible quantum exponent. For example, …”.

The phrase "for each operation delivering a result in decimal floating-point format”, simply identifies the operations (namely the ones with decimal results) to which the table applies.

- Jim Thomas

> On Oct 24, 2020, at 9:32 AM, Fred J. Tydeman <tydeman at tybor.com> wrote:
> 
> I believe that "exact" should be added before "result" in 5.2.4.2.3#7:
> 
> The following table shows, for each operation delivering a result in decimal floating-point format,
> how the preferred quantum exponents of the operands, Q(x), Q(y), etc., determine the preferred
> quantum exponent of the operation result.
> 
> 
> IEEE-754 says that if the result is inexact, use the smallest exponent so as
> to get the maximum precision (so that table does not apply).
> 
> ---
> Fred J. Tydeman        Tydeman Consulting
> tydeman at tybor.com      Testing, numerics, programming
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