Re: Errata for IEEE 754-2008 -- precision 1

[Vincent Lefevre <vincent@xxxxxxxxxx>]

On 2009-03-31 16:15:55 -0400, Michel Hack wrote:
> Vincent was right when he considered taking the parity of the
> exponent into account -- for Binary, but not for Decimal or Hex.

I did not consider taking the parity of the exponent into account,
and I think this is useless in practice. AFAIK, the only advantage
of such a choice would be to balance round-up with round-down, as
you said. But this is a nice feature only for arithmetic formats.
For output, this is not needed and would be a bit awkward, IMHO.

And if a user really wants to define an arithmetic format in
precision 1, this is probably because more precision is not needed
and in such a case, the user probably doesn't care about the balance
between round-up and round-down (which would occur only in a few
cases: the halfway cases).

-- 
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.org/>
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