Re: Regarding digits function

[Karim Belabas <Karim.Belabas@math.u-bordeaux.fr>]

* John Cremona [2015-12-10 11:26]:
> On 10 December 2015 at 10:13, Bill Allombert
> <Bill.Allombert@math.u-bordeaux.fr> wrote:
> > On Thu, Dec 10, 2015 at 02:35:33PM +0530, chandra sekaran wrote:
> >> Hi,
> >>
> >> digits(0) is giving  empty vector.  It should give [0].
> >> Am i correct or wrong?
> >
> > No, this is expected: this is consistent with binary(0).
> > The idea is to remove all leading zeros.
> 
> That is certainly the mathematically pure answer, but in Real Life we
> strip leading 0s except for 0 itself, since we do not like empty
> strings representing integers.

Yes, our convention is that 0 has no digits.

I just checked that both Maple (convert) and Mathematica (IntegerDigits)
adopt another one; e.g. convert(0,base,2) yields [0].

> Perhaps the documentation could point this out?

Done in 'master'.

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
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