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Author oscarbenjamin
Recipients agthorr, belopolsky, christian.heimes, ethan.furman, gregory.p.smith, mark.dickinson, oscarbenjamin, pitrou, ronaldoussoren, sjt, steven.daprano, stutzbach, terry.reedy, tshepang, vajrasky
Date 2013-08-22.11:57:50
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Message-id <CAHVvXxTFriBV9ST5WjSq=jLcdW=-uEL_anTBHJQYHSh4NdrxdQ@mail.gmail.com>
In-reply-to <52157AB8.6000308@pearwood.info>
Content 
On 22 August 2013 03:43, Steven D'Aprano <report@bugs.python.org> wrote:
>
> If Oscar is willing, I'd like to discuss some of his ideas off-list, but that may take some time.

I am willing and it will take time.

I've started reading the paper that Raymond Hettinger references for
the algorithm used in his accurate float sum recipe. I'm not sure why
yet but the algorithm is apparently provably exact only for binary
radix floats so isn't appropriate for decimals. It does seem to give
*very* accurate results for decimals though so I suspect the issue is
just about cases that are on the cusp of the rounding mode. In any
case the paper cites a previous work that gives an algorithm that
apparently works for floating point types with arbitrary radix and
exact rounding; it would be good for that to live somewhere in Python
but I haven't had a chance to look at the paper yet.
History
Date User Action Args
2013-08-22 11:57:50oscarbenjaminsetrecipients: + oscarbenjamin, terry.reedy, gregory.p.smith, ronaldoussoren, mark.dickinson, belopolsky, pitrou, agthorr, christian.heimes, stutzbach, steven.daprano, sjt, ethan.furman, tshepang, vajrasky
2013-08-22 11:57:50oscarbenjaminlinkissue18606 messages
2013-08-22 11:57:50oscarbenjamincreate