On Sat, Jul 18, 2009 at 3:31 PM, Vinzent
Steinberg<[email protected]> wrote:
>
> On Jul 8, 10:38 pm, Fredrik Johansson <[email protected]>
> wrote:
>> On Wed, Jul 8, 2009 at 10:07 PM, Ondrej Certik<[email protected]> wrote:
>> > so I am confused about those digits at the end. But apparently they
>> > can't be trusted.
>>
>> This is arguably not a bug. It's hard to determine whether a given
>> decimal expansion that goes "999..." or "000..." should be rounded up
>> or down. The only way to do it is to continue calculating until a
>> digit other than 9 or 0 appears, and in general it's impossible to
>> tell whether trying will get you stuck in an infinite loop.
>>
>> You could write function (or add an evalf option) that tries to find n
>> digits, and make it look for trailing 9's or 0's, but you'd have to
>> implement some stopping criterion.
>
> I think we should just add an option that specifies the maximal number
> of trailing 9's or 0's to look for, and set a reasonable default for
> it.

I think there is no reasonable default, as this example shows. I would
just leave it as is, I didn't realize there is no easy fix.

Ondrej

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