Well... I think we can agree that if ?. were replaced with 0: that
that would not be random enough.

So there has to be a better way of talking about this issue.

If the current test suite is looking for hard coded results from ?. --
and I think it does -- then of course changing the ?. implementation
would require careful update of the test suite, and this would become
an ongoing future issue if the underlying implementation changed. So I
think that that level of effort is what you are talking about??

Thanks,

-- 
Raul

On Sun, Jul 19, 2020 at 11:58 AM bill lam <[email protected]> wrote:
>
> Even ?. is not good, it won't change. Its purpose is to provide repeatable
> random data for testing, it doesn't matter if it is not random enough.
>
> On Sun, Jul 19, 2020 at 11:41 PM Julian Fondren <[email protected]>
> wrote:
>
> > On 2020-07-19 10:31, Brian Schott wrote:
> > > Yes, I see the problem you are describing better now.
> > > This behavior for powers of 2 is dissimilar with other power bases.
> > > It suggests a flaw in the algorithm for ?. .
> > >
> > >
> > >    ?.2^11
> > > 1826
> > >    ?.2^12
> > > 1826
> > >    ?.2^13
> > > 1826
> > > NB. compared to the following
> > >    ?.3^11
> > > 35532
> > >    ?.3^12
> > > 212679
> > >    ?.3^13
> > > 1275561
> >
> >     #@~."1 (?."0 ,: ?.) 2^i.20
> > 7 18
> >     #@~."1 (?."0 ,: ?.) 3^i.20
> > 13 20
> >
> > It's only not as obvious with powers of 3.
> > ----------------------------------------------------------------------
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> >
> ----------------------------------------------------------------------
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