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From: pereira@radish.research.att.com (Fernando Pereira)
Subject: Re: finite-state automata operations in Prolog (ANNOUNCE)
In-Reply-To: vannoord@let.rug.nl's message of Thu, 16 Mar 1995 13:09:44 GMT
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References: <1995Mar16.130944.22507@let.rug.nl>
Date: Fri, 17 Mar 1995 04:32:58 GMT
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In article <1995Mar16.130944.22507@let.rug.nl> vannoord@let.rug.nl (Gertjan van Noord) writes:
   A few weeks ago there was some discussion whether or not finite
   state automaton operations (intersection, determinization, minimalization,
   intersection..) could be efficiently implemented in Prolog.
   Fernando Pereira doubted this; although some others were less pessimistic.
Let me make this clear. Once upon a time I used to have such a set of
tools in Prolog, although they were never as nicely packaged as
yours. I did spend some time trying to make them efficient, but I
moved to C (gag!) when I started working with machines with 10^4-10^6
states/transitions and alphabets of 10^4-10^5 symbols. Incidentally,
the textbook algorithms have huge overheads on very large alphabets,
nontrivial changes are needed to make them practical. 

--
Fernando Pereira
2B-441, AT&T Bell Laboratories
600 Mountain Ave, PO Box 636
Murray Hill, NJ 07974-0636
pereira@research.att.com
1-908-582-3980


