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 <elro...@elronnd.net> 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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