I was just about to say that, Henry.

Ancillary pages are intended to be linked from multiple NuVoc pages. I
thought there might be a need for a new one to address the matter of this
thread. But [[Vocabulary/Constants]]
 https://code.jsoftware.com/wiki/Vocabulary/Constants
seems to be its natural home for now.

Note that the last section:
 https://code.jsoftware.com/wiki/Vocabulary/Constants#Further_reading
promises to answer Raul's question, but links to a missing page …or is it a
placeholder?

Some NuVoc pages link into Pipermail, as a temporary measure, until someone
has the time to draw threads together.
For forum members who haven't used Pipermail, the link to the present
thread is:
 https://www.jsoftware.com/pipermail/general/2021-October/038701.html

On Sat, 23 Oct 2021 at 13:44, Henry Rich <[email protected]> wrote:

> Constants
>
> Henry Rich
>
> On Sat, Oct 23, 2021, 2:03 PM Raul Miller <[email protected]> wrote:
>
> > I guess the question is: which wiki page should this be documented in?
> >
> > (If it's not already -- I guess another question is what should I
> > search on to attempt to find such documentation?)
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Sat, Oct 23, 2021 at 5:44 AM Henry Rich <[email protected]> wrote:
> > >
> > > You might have a point, but I don't think it's worth taking the risk of
> > > breaking existing code to make the change.  If you want a float, add a
> > > decimal point.
> > >
> > > Numbers close to IMAX are always troublesome because of tolerance.
> > >
> > > Henry Rich
> > >
> > > On 10/23/2021 4:13 AM, ethiejiesa via General wrote:
> > > > The issue I find surprising is that integer literals in the range
> > > > 16b8000000000000000 to 16b80000000000004ff, i.e. INT_MAX+1 to
> > INT_MAX+1024, all
> > > > parse into the integer precision 9223372036854775807, i.e. INT_MAX.
> > This is not
> > > > the same thing as (<:2^63) which has floating precision.
> > > >
> > > > My expectation was that non-exact representations for (2^63x) and
> > above---
> > > > e.g. 16b8000000000000000---would parse into floating precision
> numbers.
> > > >
> > > > As it stands, this means that integer precision values equal to
> > > > 16b7fffffffffffffff cannot be trusted and must be handled specially,
> as
> > > > demonstrated nicely in Raul's examples below.
> > > >
> > > > Henry Rich <[email protected]> wrote:
> > > >> 16b8000000000000401 cannot be exactly represented.  There is a band
> > of floats near 2^63 that are converted to (<:2^63).
> > > >>
> > > >> Henry Rich
> > > >>
> > > >>
> > > >>
> > > >> On 10/23/2021 1:42 AM, Raul Miller wrote:
> > > >>> I do not see why I should expect these to be the same number:
> > > >>>
> > > >>>      2^.92233720368547768323
> > > >>> 66.3219
> > > >>>      2^.16b8000000000000401
> > > >>> 63
> > > >>>
> > > >>> One is larger than can be represented using a 64 bit integer, and
> so
> > > >>>
> > > >>>      datatype 92233720368547768323
> > > >>> floating
> > > >>>
> > > >>> That said, I do think that there's a problem with the other one.
> That
> > > >>> one is also larger than can be represented using a 64 bit signed
> > > >>> integer:
> > > >>>
> > > >>>      (2^63x)-16b8000000000000401
> > > >>> 1
> > > >>>      (2^63x)-16b8000000000000000
> > > >>> 1
> > > >>>      (2^63x)-16b7fffffffffffffff
> > > >>> 1
> > > >>>
> > > >>> So there's a certain range of numbers here which get treated ...
> > oddly.
> > > >>>
> > > >>> Thanks,
> > > >>>
> > > >
> > > >
> ----------------------------------------------------------------------
> > > > For information about J forums see
> http://www.jsoftware.com/forums.htm
> > >
> > >
> > > --
> > > This email has been checked for viruses by AVG.
> > > https://www.avg.com
> > >
> > > ----------------------------------------------------------------------
> > > For information about J forums see http://www.jsoftware.com/forums.htm
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> >
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm

Reply via email to