er, red faced apologies. JESS already has a very nice backchaining capability already built in. Sorry 'bout that. (Gee, this JESS has a whole lotta suff!!) Steve
On Saturday 26 May 2007 16:40, Stephen D Lindner wrote: > Hi Piotr, > IMHO, the difference between Prolog and JESS is an important insightful > question. The difference is really the difference between backchaining > (PROLOG) and forward chaining (JESS/RETE families). So this begs the > question, "What is backchaining and forward chaining?". > > If this is your first time with these concepts, don't feel bad if you need > to ask several people. Maybe one of us will say the right thing that will > put everything together for you. Here is my short attempt. > > For the moment, try to think of both as just production rules in a > grammar...like in yacc or lex or something. A backchaining grammar is one > that starts with the goal rules (e.g. PROGRAM) and backchains to the > commas, numbers, and reserved words (as in PROLOG). Recall that these are > also known as the token symbols. OTOH a forward chaining system starts with > the token symbols and tries to choose the best production rules to use (aka > "fire" as in JESS/RETE) to get to the detection of a complete PROGRAM. Also > BTW, this is sometimes referred to as top-down (PROLOG) vs bottom-up > (JESS), respectively. > > I hope the above thumbnail explanation can help. But I am forced to add one > thing that may seem very confusing. You can actually use either language to > do chaining in the wrong direction. You can use PROLOG to fake forward > chaining. And you can use JESS/RETE to fake backchaining. In fact, some > RETE systems (e.g. old "big ART" and Paul Haley's rete) have backchaining > already built in. (Apologies to Ernest Friedman-Hill if he added this since > the last time I looked.) Over the years of consulting that I have done, I > have found people backchaining with a forward-chain-only rete without > actually knowing it! > > At any rate, I hope my brief explanation can help. > Best of luck with your thesis. > Steve Lindner > > On Saturday 26 May 2007 09:49, Piotr Antkowiak wrote: > > Hello, > > > > I will write my master work about Jess and Prolog > > Title: "Jess - a Java software package for rule-based programing." > > > > I will be compare Prolog and Jess. On mine university we learned only > > Prolog and now I try rewrite some program from Prolog to Jess. > > > > My first program (I have still problem with writing this rule > > "2)the golfer to Fred's immediate right is wearing blue pants;" > > in my Prolog program) > > Golfer problem from "Jess in Action" book > > http://antkowiak.fr.pl/jess/golfers.pro (mine script) > > http://antkowiak.fr.pl/jess/golfers.clp (script form book) > > > > My request: > > maybe somebody rewrite some program from Prolog to Jess or fome Jess to > > Prolog and have some conclusions why Jess/Prolog is better or other > > conclusions about those programs. I will be thankful for all indicators. > > > > I can using google ;-) and I read few article about this but it is too > > little for me. > > > > Thank You very much for any help. > > > > Ps. I apologize for my English > > -------------------------------------------------------------------- > To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' > in the BODY of a message to [EMAIL PROTECTED], NOT to the list > (use your own address!) List problems? Notify [EMAIL PROTECTED] > -------------------------------------------------------------------- -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
