Re: Motion P1788/M0015.01: Definition_of_decorations: Up for discussion
On 2010-04-28 23:46:52 -0700, Dan Zuras Intervals wrote:
> > On 28 Apr 2010, at 15:40, Dan Zuras Intervals wrote:
> > > The definitions of the 'bounded' properties then become
> > >
> > > boundedTrue = {there exists x in xx such that the
> > > nearest representable number for f(x) is
> > > finite in the current working precision.
> > > That is, that the 754 isBounded(f(x)) is
> > ??
> > > true.}
> > >
> > > boundedFalse = {there exists x in xx such that the
> > > nearest representable number for f(x) is NOT
> > > finite in the current working precision.
> > > That is, that the 754 isBounded(f(x)) is
> > ??
> > > false.}
> >
> > Do you mean isFinite() ? There is no isBounded() in 754.
> >
> > John
>
> Oops. Yes. My mistake. Thanks. - Dan
You also need to say which rounding direction attribute you consider.
Also the definition is rather strange if x is a machine number.
Think about cases like f = tan. Function tan is not bounded, but
in practice f(x) is finite for finite machine numbers x.
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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