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From: sasgwb@mozart.unx.sas.com (Gary Black)
Newsgroups: comp.ai
Subject: Arc COnonsistency On > Hyperarcs...
Message-ID: <1990Jul03.144321.10073@unx.sas.com>
Date: 3 Jul 90 14:43:21 GMT
Sender: sasgwb@unx.sas.com (Gary Black)
Distribution: na
Organization: SAS Institute Inc.
Lines: 14

I've seen most of the good algorithms for arc consistency (AC1, AC2, AC3,
AC4, etc.) and they all are presented in examples using ONLY BINARY
CONSTRAINTS.  On n-ary constraints, these algorithms seem to rapidly get
prohibitively expensive.

My question is:  Is anyone aware of AC algorithms which can handle
hyperarcs? For example, given a constraint net with 3 nodes, A, B, and
C, and a constraint A + B = C, how do we perform AC on this net without
looking at the power set of the domains of A, B and C?  Is it even
possible?

Thanks in advance for any helpful comments.

Gary