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Re: min / max and empty intervals



> Date: 09 Jun 2011 09:51:10 +0100
> From: "N.M. Maclaren" <nmm1@xxxxxxxxx>
> To: rbk@xxxxxxxxxxxx
> Cc: Dan Zuras Intervals <intervals08@xxxxxxxxxxxxxx>, rbk@xxxxxxxxxxxxx, stds-1788@xxxxxxxxxxxxxxxxx
> Subject: Re: min / max and empty intervals
> 
> On Jun 9 2011, Ralph Baker Kearfott wrote:
> >On 6/8/2011 9:12 PM, Dan Zuras Intervals wrote:
> >>
> >> =09Makes perfect sense.  I hadn't thought about it
> >> =09well enough to figure that out.  That's what
> >> =09comes of having no experience in this stuff.  - Dan
> >
> >Ahhh, but your experience in other matters complements experience
> >of others in the group, and is very welcome.

	That is very kind of you, Ralph.

> 
> Nobody knows everything.  On this matter, Missing is not quite the
> same as Unknown, because it is treated differently in reductions
> and in fill-in interpolations.  Outside those, it is the same.
> 
> This whole matter is thoroughly confusing :-(
> 
> 
> Regards,
> Nick Maclaren.

	Yes, Nick, it is confusing.
	And I know you have lived in both worlds & dealt with these
	problems.
	754 is infamous for conflating lots of different things under
	the name NaN.
	Alas, some 3 decades of floating-point experience mostly with
	754 has led me to ignore the differences to my current
	detriment.
	Still, I am glad that 1788 has things like entire & empty to
	stand in for some of these things.
	NaNs have been a pain in the ass for my entire career.
	754 can't do without them & living WITH them is no picnic.
	If our decorations allow us to represent other interesting
	things without using anything that looks like an NaI, I would
	be happy with them.
	Indeed, if it begins to look like we NEED an NaI, my first
	thought would be: Let's make another decoration first.

	You know, that reminds me of something.
	This is totally off the subject but, Nate, you once argued for
	the need for non-standard intervals for your graphics work.
	And I know other have discussed them for solving equations.
	Have you figured something else out or is this just a subject
	for some other day?
	I remember we once kicked arouond a decoration called
	'non-standard'.
	Do we still need that?
	Or is this a subject better discussed after we have settled
	much of the other decoration issues?
	Please feel free to ignore the question if it is.

	It just came up while I was thinking about Nick's observation.

	Yours,

				    Dan