Prolog Download Binaries and Source
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CSCI: 4500/6500 Programming Languages
SWI-prolog (swipl 5.10.4-6.0.2 depending on platform) website: » http://www.swi-prolog.org/! » Mac OS X on Intel & PPC (Tiger, Leopard (46.3 MB), Snow Leopard and Lion binaries available) » Linux RPMs.
Prolog & Logic Programming
» Windows NT, XP, Vista7, 2000, 64 Bit, » Source Install !
Thanks to: William W. Clocksin, Oxford University, UK.,Jason Eisner, John Hopkins University, James Lu & Jerud Mead, Bucknell University.
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Maria Hybinette, UGA
XQuartz (X11) 2.5.0 for help & development tools. 2
Maria Hybinette, UGA
Great Prolog Tutorials !
What is Prolog?
JR Fisher s original tutorial :
http://www.csupomona.edu/~jrfisher/www/ prolog_tutorial/contents.html !
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Roman Barták s interactive tutorial:
» With help from theorem proving folks such as Robert Kowalski » Colmerauer & Roussel wrote 20 years later:
http://ktiml.mff.cuni.cz/~bartak/prolog/ !
Mike Rosner s crash course:
http://www.cs.um.edu.mt/~mros/prologcc/ !
Alain Colmeraeur & Philippe Roussel, 1971-1973
James Lu and Jerud Mead s tutorial:
Prolog is so simple that one has the sense that sooner or later someone had to discover it … that period of our lives remains one of the happiest in our memories.
http://www.cse.ucsc.edu/classes/cmps112/ Spring03/languages/prolog/PrologIntro.pdf !
James Power s tutorial: http://www.cs.nuim.ie/~jpower/Courses/ PROLOG/ (2012 not available – BUT let me know if you find it –it is a good one) 3
Maria Hybinette, UGA
What is Prolog? !
Lets look at a sample session… {saffron:ingrid:815} swipl
A declarative or logic programming language
Welcome to SWI-Prolog (Multi-threaded, Version 5.6.9) Copyright (c) 1990-2006 University of Amsterdam.
» specifies the results (describes what the results look like)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. Please visit http://www.swi-prolog.org for details.
– in contrast to a procedure on how to produce the results. !
For help, use ?- help(Topic). or ?- apropos(Word).
Based on first order predicate calculus
?- [ second']. % first compiled 0.00 sec, 596 bytes
» consists of propositions that may or may not be true !
CTRL-p moves up in command history CTRL-n next command -> edit command line history
» Not the same as variables in other languages
Maria Hybinette, UGA
repeat commands by traversing the command line history
TailReverse!
reverse([],[]). reverse([Head|Tail],X) :reverse(Tail,Y), append(Y,[Head],X). Maria Hybinette, UGA
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Maria Hybinette, UGA
solve [reverse([2],Y),
nothing
append(Y,[1],X)] solve [reverse([],X),
nothing
append(X,[2],X), append(X,[1],X)]
solve [append([],[2],[]),
append([],[1],[])]
nothing
nothing
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Deficiencies of Prolog solve [reverse([1,2],X)]
This step is wrong: we substituted X for Y, but there is already a different X elsewhere in the goal list.
nothing
solve
[ reverse([2],Y)! append(Y1,[1],X1)]!
nothing
solve [ reverse([],Y2)!
append(Y2,[2],X2)]! append(X2,[1],X1)]! solve [append([],[2],X2),!
reverse([],[]). reverse([Head|Tail],X) :reverse(Tail,Y), append(Y,[Head],X).
!
Resolution order control
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The closed-world assumption
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The negation problem
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Intrinsic limitations
nothing
append(X2,[1],X1)]!
[append([2],[1],X1)]!
solve Maria Hybinette, UGA
[]!
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Advantages: !
Prolog programs based on logic, so likely to be more logically organized and written
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Processing is naturally parallel, so Prolog interpreters can take advantage of multiprocessor machines
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SWI-Prolog ?- set_prolog_flag(history, 50). Yes 27 ?- h.
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% shows history of commands
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eats(Person1,Food1).
3 4
eats(Person1,Food),eats(Person2,Food). eats(corey,fish).
?- !!.
Programs are concise, so development time is decreased – good for prototyping
Maria Hybinette, UGA
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Maria Hybinette, UGA
Maria Hybinette, UGA
% Repeats last query
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