strange behaviour with simple decimals



On Wed, Apr 11, 2007 at 10:20:53AM -0500, Jay Belanger wrote:
> 
> "Stavros Macrakis" <macrakis at alum.mit.edu> writes:
> 
> > n 4/11/07, Henning Siebel <henning.siebel at gmx.de> wrote:
> >
> >       (%i1) 3*1.4^2;
> >       (%o1)                          5.879999999999999
> >
> > Maxima uses native 64-bit floating-point arithmetic for numbers with decimal points,
> > so rounding errors are of the order of 10^-16. 
> ...
> > This has nothing to do with Maxima,
> 
> Since it is Maxima giving the result, I'd say it has everything to do
> with Maxima.  Here, it has to do with the way that Maxima handles
> floats.
> It may be worth noting that both Axiom and my pocket calculator give
> the correct answer to 3*1.4^2.

Pocket calculators are typically programmed with base 10 floating
point.

Does axiom give teh correct answer, or just display a rounded version
of its slighly incorrect answer? ie. what happens if you say 3*1.4^2 -
588.0/100.0


-- 
Daniel Lakeland
dlakelan at street-artists.org
http://www.street-artists.org/~dlakelan