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Re: Constructors motion 30 Version 2: small amendment

> Date: Tue, 7 Feb 2012 16:30:25 +0100
> From: Vincent Lefevre <vincent@xxxxxxxxxx>
> To: stds-1788@xxxxxxxxxxxxxxxxx
> Subject: Re: Constructors motion 30 Version 2: small amendment
> 
> On 2012-02-07 04:26:01 -0800, Dan Zuras Intervals wrote:
> 
> . . .
> 
> > 	P.S. - While num2interval() takes a floating-point
> > 	number as input I'm sure that text2interval() can
> > 	be made safe by defining the output to be
> > 	[roundDown(text2num(text)),roundUp(text2num(text))].
> 
> I don't think this makes sense. What is text2num supposed to
> give? If it is a Level2 numeric value (e.g. floating-point),
> then roundDown and roundUp will not have any effect on it.

	You're quite correct.  The definition should use the
	equivalent of

	[roundDownText2num(text)),roundUpText2num(text))]

	as primitives.  There exist such primitives in 754.  - Dan

> 
> -- 
> Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)