In article
<8b356f880705041523i5d74bfd6r7e0fd751deb8a7b4 at mail.gmail.com>,
"Stavros Macrakis" <macrakis at alum.mit.edu> wrote:
> >
> > > (+ (* 1d-20 (expt 1d20 2)) (* -5.5d0 1d20) 5.2d20)?
> > >
> > > Does this produce 7d19 or something else?
> >
> > 7.000000000000013E19
> >
>
> I suspect this is a bug in LispWorks' print or read algorithm, since 7e19 is
> the IEEE arithmetic result and is exactly representable as an IEEE double,
> since it = 2^19 * 133514404296875
>
> What do you get for
>
> (* (expt 2 19) 133514404296875 1.0d0)
> or
> (* 70000000000000000000 1.0)
> or
> (- 70000000000000000000 7.0e19)
> or
> (list 1.0e-20 5.5 5.2e+20 )
> ?
>
>
CL-USER 1 > (* (expt 2 19) 133514404296875 1.0d0)
7.0D19
CL-USER 2 > (* 70000000000000000000 1.0)
7.0E19
CL-USER 3 > (- 70000000000000000000 7.0e19)
0.0
CL-USER 4 > (list 1.0e-20 5.5 5.2e+20 )
(1.0E-20 5.5 5.2E20)
> What about
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