evalf()/Digits bugs

Phil Mendelsohn mend0070 at tc.umn.edu
Tue Jan 8 14:13:03 CET 2002

On Mon, 7 Jan 2002, Richard B. Kreckel wrote:

> Oh, if you worry about that, then throwning away digits in the output is
> not going to help since it is merely cosmetic.  If we could have
> two digits, then compared to 3.3, you are saying that 3.333 is better than
> 3.3334.  Why bother?

Sorry for sticking my oar in, but I think the reason the one inaccurate
answer is better than the other is a human one, not a machine or a
precision one.  Either way you should describe the output behavior
concisely, and with the current behavior, the description that should be
used is

"GiNaC gives you meaningless garbage at the end of your output under <x>

Not exactly something that sounds like a feature. ;)

It's easier (I think) to spot that the number of digits isn't right, but
nice to know that at least what you *do* see is correct.

Just another county heard from.


"Trying to do something with your life is like
sitting down to eat a moose." --Douglas Wood

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