Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: DRAFT position paper

I suggest to use D_0 (Nate) or ILL (Arnold) to only indicate really illformed intervals (with inf > sup, e.g. and decorate with D_1 resp. EMP in case of undefined or empty operand. Note, that the result of an intersection of disjoint intervals is (emptyset, D_4)in example 11, hence the empty set is not always bad. 

I further suggest to change formula (33) to:
D_4/D_4 = D_2
because the division provides the decoration D_2 (somewhere undefined)

regards
Juergen

Am 13.12.2010 03:11, schrieb Kreinovich, Vladik:

Honestly, I am waiting for John Pryce's formalization that he promised a few days ago. I think it will clarify the issue.

-----Original Message-----
From: stds-1788@xxxxxxxx [mailto:stds-1788@xxxxxxxx] On Behalf Of Michel Hack
Sent: Sunday, December 12, 2010 6:37 PM
To: stds-1788
Subject: Re: DRAFT position paper

The longer the Arnold-Nate PingPong match lasts, the more I become
convinced that it is a battle about nothing.  The decoration at the
end of a long computation gives a summary of what may have gone wrong,
and to find out the detail, one retries it, checking at every step, or
(if the system supports it) in a mode that makes certain conditions
trigger a synchronous trap, with operands made available to the trap
handler.  So Arnold's scheme lumps certain conditions together that
Nates' distinguishes -- but I doubt ALL distinctions are made, so in
general operands of suspicious operations have to be inspected anyway,
at which point full discrimination is possible.

So if Arnold's scheme has other advantages, they should not be discarded
because of this quibble between undefined, ill-defined and empty.

Michel.
---Sent: 2010-12-13 01:49:34 UTC


--
-
     o          Prof. Dr. J. Wolff v. Gudenberg, Informatik II
    / \          Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg
InfoII o         Tel.: +49 931 / 31 86602
  / \  Uni       E-Mail: wolff@xxxxxxxxxxxxxxxxxxxxxxxxxxx
 o   o Wuerzburg