[Gcl-devel] Re: GCL bugs (decode-float, rationalize, expt)

[Raymond Toy]

Stavros Macrakis wrote:
> Incorrect.  (rationalize 1.0e-320) should be 1/x, where x is
> somewhere near 10^320, and (float (rationalize 1.0e-320) should be

FWIW, clisp has a good implementation of rational (or was that 
rationalize?)  I believe cmucl has a lisp implementation of the same 
algorithm.

> > > (decode-float 1.0e-320)
> >
> > 0.50000000000022471
> > -1022
> > 1.0
>
>
> Incorrect.  0.5 * 2^-1022 = 1.1e-308, not 1.0e-320.
> Correct answer is roughly .49, -1062, 1.0

FWIW, cmucl says 0.98828125d0, -1063

Ray