[Python-ideas] Fix some special cases in Fractions?

[Neil Girdhar]

On Thu, Aug 30, 2018 at 7:13 AM Paul Moore <p.f.moore at gmail.com> wrote:

> (You're still not fixing your mail headers. Please do, it's hard to be
> bothered responding if I keep having to fix your mails in order to do
> so).
>

Sorry about that, I don't understand where it's coming from.   I'm never
using google groups. I'm only replying to the emails that are sent to me.
I guess gmail's reply-all is gathering the google groups mail from the
thread.


> On Thu, 30 Aug 2018 at 11:28, Neil Girdhar <mistersheik at gmail.com> wrote:
> >
> > But I'm only asking for fractional powers of -1, 0, and 1.  Is that
> really a complex issue?
>
> Yes. (Even ignoring the oh-so-tempting complex number joke ;-)). As
> has been seen here there's no agreement on the "right" choice of which
> root of -1 to choose. Or possibly more accurately, no-one else is
> agreeing with your suggestion that we choose a different option for
> the case you're arguing over.
>
> And to be 100% precise, you asked for the results of three *very
> specific* calculations to change. I guess you actually want something
> more general - or are you really OK with (for example)
> Fraction(-1,1)**Fraction(2,3) changing as you request, but
> Fraction(-2,1)**Fraction(2,3) remaining as it currently is? You still
> haven't clarified (no-one has particularly asked yet - you may
> consider this a request to do so if you like) how you propose in
> general that the result of
>
>     Fraction(-1,1) ** Fraction(a, b)
> and/or
>     Fraction(1,1) ** Fraction(a, b)
> or maybe even more generally
>     Fraction(c,d) ** Fraction(a,b)
>
> would change. What exactly are the special cases you want to define
> different results for? What is the process for choosing the result?
>
> > You are right that the fractional power of -1 and 1 has multiple values,
> but the fractional power of zero has a unique value.
>
> And that part of your proposal has not generated much controversy.
> Maybe if you proposed only that, you might get that change made? I
> haven't considered the ramifications of that because the discussions
> about -1 are obscuring it, but it might be relatively uncontroversial.
>
> Paul
>
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