True, but that is not an example of the kind of test being performed here.

Thanks,

-- 
Raul

On Mon, Jan 10, 2022 at 10:08 AM Elijah Stone <[email protected]> wrote:
>
>     a=. x:1p1
>     a =!.0 ^.^:_1 ^.a
> 0
>
> This is what I mean when I say 'the properties being tested are not tested
> on functions that produce irrationals'.  We are unable to demonstrate that
> a = f^:_1 f a, because even if a is represented exactly, f may be
> approximate.
>
>   -E
>
> On Mon, 10 Jan 2022, Raul Miller wrote:
>
> > Even there, floating point numbers are just approximations of
> > irrationals, and x: works on those approximations just fine.
> >
> > The limitations of x: are (1) performance -- you take a performance
> > (and memory) hit using arbitrary precision representation, and (2)
> > complex numbers. We currently do not have an arbitrary precision
> > representation of complex numbers.
> >
> > Some of this might change in the future, though. For example, while
> > there will always be a performance and memory penalty, that penalty
> > can be significantly reduced.
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Mon, Jan 10, 2022 at 8:53 AM Elijah Stone <[email protected]> wrote:
> >>
> >> On Mon, 10 Jan 2022, Raul Miller wrote:
> >>
> >> > x:
> >>
> >> Good point.  I was thinking that they might want to represent irrationals.
> >> But I guess that doesn't matter so long as the properties being tested are
> >> not tested on functions that produce irrationals.
> >>
> >>   -E
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