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Re: round bug
* From: Per Bothner <per@xxxxxxxxxxx>
* Date: Sat, 22 May 2004 08:38:43 -0700
* Subj: Re: round bug
>> Still, do you think it is right that the "round to even" discipline of ROUND
>> procedure is applied to the ~F directive of FORMAT procedure?
| Yes, I think that is the right thing to do. Is there any reason to do
| otherwise? There may be an issue with "generally accepted accounting
| principles" - that seems to ring a bell. But I don't remember.
| The Common Lisp hyperspec says:
When rounding up and rounding down would produce printed values
equidistant from the scaled value of arg, then the implementation is
free to use either one. For example, printing the argument 6.375 using
the format ~4,2F may correctly produce either 6.37 or 6.38.
| So round-to-even is certainly compatible with Common Lisp.
I had known only the standard rounding.
And I did not understand why such an odd method should be used.
Thank you for making me know the Gaussian rounding besides the standard