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Re: Motion P1788/M0015.01: Definition_of_decorations: Up for discussion



> Date: Thu, 29 Apr 2010 10:10:12 +0200
> From: Vincent Lefevre <vincent@xxxxxxxxxx>
> To: stds-1788@xxxxxxxxxxxxxxxxx
> Subject: 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.

	Yep.

> 
> 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.
> 
> -- 
> Vincent Lefèvre

	Well, as I keep saying, this is not a motion 15 issue.

	Which is good if there are still bugs to be worked out
	in it. :-)

	Back to the drawing board...


				Dan