Yes -- and you did actually express the reason, it's spelled out on
the page on extended and rational arithmetic (which is becoming
increasingly difficult to find, what with the nuvoc changes):
https://www.jsoftware.com/help/dictionary/dictg.htm

Thanks,

-- 
Raul

On Tue, Jan 26, 2021 at 1:44 PM Roger Hui <[email protected]> wrote:
>
> Ah, I stand corrected.  There _are_ rational infinities, but you have to
> make them deliberately using x: (or some other means).  e.g.
>
>    (x: _) <.
> 83121579216557378445487899878180864668798711284981320763518679672151497189239x
> 83121579216557378445487899878180864668798711284981320763518679672151497189239
>
>    (x: __) >.
> 83121579216557378445487899878180864668798711284981320763518679672151497189239x
> 83121579216557378445487899878180864668798711284981320763518679672151497189239
>
> I should have thought more before I wrote my first reply.  For % to be
> closed on rationals rational infinities are required.
>
>    % 0 3r4
> _ 4r3
>    3!:0 % 0 3r4
> 128
>
> Sorry.
>
>
>
>
> On Tue, Jan 26, 2021 at 10:33 AM 'Sergey Kamenev' via Beta <
> [email protected]> wrote:
>
> > I make calculations on elliptic curves on finite fields.
> > In elliptic curves exists so-called "point in infinity".
> >
> > This is how I noticed this problem.
> >
> > 26.01.2021 18:52, Roger Hui пишет:
> > > The reason for these results, dating from very early days and old old
> > > versions, is that there are no rational or extended integer infinities.
> > In
> > > float F rat (or rat F float), the rule is to convert the rat into a
> > float,
> > > and then apply the F.  Therefore the results in your message are
> > "correct".
> > >
> > >
> > > On Tue, Jan 26, 2021 at 3:16 AM 'Sergey Kamenev' via Beta <
> > > [email protected]> wrote:
> > >
> > >> Hi!
> > >>
> > >> Min and Max function makes unnecessary conversion of type when compared
> > to
> > >> infinity and loses significant information.
> > >>
> > >> Example:
> > >>
> > >>
> > >> _ <.
> > >>
> > 83121579216557378445487899878180864668798711284981320763518679672151497189239x
> > >> 8.31216e76
> > >>
> > >> Should be:
> > >>
> > 83121579216557378445487899878180864668798711284981320763518679672151497189239
> > >>
> > >> __ >.
> > >>
> > 83121579216557378445487899878180864668798711284981320763518679672151497189239x
> > >>
> > >> 8.31216e76
> > >>
> > >> Should be:
> > >>
> > 83121579216557378445487899878180864668798711284981320763518679672151497189239
> > >>
> > >> Nice day!
> > >> Sergey
> > >> ----------------------------------------------------------------------
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> > >>
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