Newsgroups: comp.constraints
Path: cantaloupe.srv.cs.cmu.edu!europa.chnt.gtegsc.com!news.sprintlink.net!news.ecrc.de!ecrc!news
From: micha@ecrc.de (Micha Meier)
Subject: Re: Question: constraint terminology
Message-ID: <DB6Mpw.Jv9@ecrc.de>
Sender: news@ecrc.de
Reply-To: micha@ecrc.de
Organization: European Computer-Industry Research Centre
References: <1995Jul3.124452.21746@ilog.fr>
Date: Tue, 4 Jul 1995 08:10:44 GMT
Lines: 21

The term 'global constraints' has been used in CHIP to actually denote
constraints that subsume a set of other constraints. It does not necessarily
mean that complete global consistency is being achieved, but just the
fact that more consistency is being achieved than by considering
each constraint in this set separately. This concerns mainly
finite domain constraints where global consistency is hard to obtain.
The term 'global constraints' is quite misleading, but once you
know what it is supposed to mean, you get used to it :-)
Note that you can have several global constraints with the same
declarative reading, but with different algoritm being used
and thus different levels of consistency being achieved.

--Micha

---
Micha Meier			------------------------------------------------
ECRC, Arabellastr. 17		The opinions expressed above are private
D-81925 Munich 81		and may not reflect those of my employer.
micha@ecrc.de, Tel. +49-89-92699-108, Fax  +49-89-92699-170


