Prolog - Revision history

Wikisailor: /* Introduction to Prolog by dissecting Learn Prolog Now! book */

2025-05-23T22:00:05Z

Introduction to Prolog by dissecting Learn Prolog Now! book

← Older revision		Revision as of 22:00, 23 May 2025
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	playsAirGuitar(jody).		playsAirGuitar(jody).
	party.		party.
	What it does not say is that if I want to run that on my own computer it will not work because I would have to either write it in a text file or enter consult(user). SWI Prolog the changes the prompt to \|: (pipe colon) with ctrl to exit, so I then type in the five facts and press ctrl + d it will then return me to the ?- prompt so I can then ask the questions like		What it does not say is that if I want to run that on my own computer it will not work because I would have to either write it in a text file or enter consult(user). SWI Prolog the changes the prompt to \|: (pipe colon) with ctrl+D to exit, so I then type in the five facts and press ctrl + D it will then return me to the ?- prompt so I can then ask the questions like
	?- playsAirGuitar(mia).		?- playsAirGuitar(mia).
	It should return true. To be fair the simply-logical book at the first website has an interactive widget on the page and it does not need to enter the consult mode. It does not expicitly say that the termination character is the dot		It should return true. To be fair the simply-logical book at the first website has an interactive widget on the page and it does not need to enter the consult mode. It does not expicitly say that the termination character is the dot. The CTRL+D is the end of line in a Linux shell, if swipl is running on Windows it would be a CTRL+Z because that is the Windows EOL

	The second example also had a bit of difficulty (for me) in that I didn't see the <space> between the :- and the next part.		The second example also had a bit of difficulty (for me) in that I didn't see the <space> between the :- and the next part.
	consult(user). # you need this line if using a ~~linux~~ shell		consult(user). # you need this line if using a Linux shell

	happy(yolanda).		happy(yolanda).

Wikisailor: /* Introduction to Prolog by disecting Learn Prolog Now! book */

2025-05-23T12:01:57Z

Introduction to Prolog by disecting Learn Prolog Now! book

← Older revision		Revision as of 12:01, 23 May 2025
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	My notes on the book that is free on the https://lpn.swi-prolog.org website.		My notes on the book that is free on the https://lpn.swi-prolog.org website.

	==Introduction to Prolog by ~~disecting~~ Learn Prolog Now! book==		==Introduction to Prolog by dissecting Learn Prolog Now! book==

	To be fair to the authors by Patrick Blackburn, Johan Bos, and Kristina Striegnitz they do a good job of introducing prolog and anything that i write here should not detract anyone from reading their book as their's is the proper book and this is just my notes that i make as i read the book i may make an observation that the authors then make as well. Anyone else reading this should only be doing so in conjunction with the actual book on https://lpn.swi-prolog.org/lpnpage.php?pagetype=html&pageid=lpn-htmlse1		To be fair to the authors by Patrick Blackburn, Johan Bos, and Kristina Striegnitz they do a good job of introducing prolog and anything that i write here should not detract anyone from reading their book as their's is the proper book and this is just my notes that i make as i read the book i may make an observation that the authors then make as well. Anyone else reading this should only be doing so in conjunction with the actual book on https://lpn.swi-prolog.org/lpnpage.php?pagetype=html&pageid=lpn-htmlse1
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	loves(marsellus,X), woman(X).		loves(marsellus,X), woman(X).
	In this query we ask it to return instances that have loves(marcellas), (AND) woman (so marsellus's woman) although there are 3 instances of woman there is only one instance of marsellus and that instance happens to have a woman in this case mia so mia is the one and only return value in X		In this query we ask it to return instances that have loves(marcellas), (AND) woman (so marsellus's woman) although there are 3 instances of woman there is only one instance of marsellus and that instance happens to have a woman in this case mia so mia is the one and only return value in X
			The next bit adds the line about jealousy and using rules with variables, telling exactly what this next line does require a bit of thought.
			jealous(X,Y):- loves(X,Z), loves(Y,Z).
			I read this as saying X is jealous of Y if Xs loves Z and Y loves Z.

Wikisailor: /* General Concept */

2025-05-21T18:59:15Z

General Concept

← Older revision		Revision as of 18:59, 21 May 2025
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	The concept of Prolog is that it is rules based rather than the more common procedural based languages like C. The focus is more on defining the problem as opposed to defining a solution by creating rule and facts to form a knowledge base		The concept of Prolog is that it is rules based rather than the more common procedural based languages like C. The focus is more on defining the problem as opposed to defining a solution by creating rule and facts to form a knowledge base

			==[[My notes on Learn Prolog Now!]]==

			My notes on the book that is free on the https://lpn.swi-prolog.org website.

	==Introduction to Prolog by disecting Learn Prolog Now! book==		==Introduction to Prolog by disecting Learn Prolog Now! book==

Wikisailor: /* Introduction to Prolog */

2025-05-21T18:55:32Z

Introduction to Prolog

← Older revision		Revision as of 18:55, 21 May 2025
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	==Introduction to Prolog==		==Introduction to Prolog by disecting Learn Prolog Now! book==

			To be fair to the authors by Patrick Blackburn, Johan Bos, and Kristina Striegnitz they do a good job of introducing prolog and anything that i write here should not detract anyone from reading their book as their's is the proper book and this is just my notes that i make as i read the book i may make an observation that the authors then make as well. Anyone else reading this should only be doing so in conjunction with the actual book on https://lpn.swi-prolog.org/lpnpage.php?pagetype=html&pageid=lpn-htmlse1

	In one of the books in the intro pages it talks about setting up a list of fact in a Knowledgebase or KB		In one of the books in the intro pages it talks about setting up a list of fact in a Knowledgebase or KB
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	If we now add space semincolon it returns the next instance and it still doesn't return us to the ?-. The third and final woman is shown we press semicolon one more time but as it is the last result from the query so as soon as it is output the ?- is displayed. There a few things to note here.		If we now add space semincolon it returns the next instance and it still doesn't return us to the ?-. The third and final woman is shown we press semicolon one more time but as it is the last result from the query so as soon as it is output the ?- is displayed. There a few things to note here.
	* Variables in Prolog are anything starting with an upper case letter (which would explain why playAirGuitar and the others have a lower case first letter but the Air and Guitar both had upper case)		* Variables in Prolog are anything starting with an upper case letter (which would explain why playAirGuitar and the others have a lower case first letter but the Air and Guitar both had upper case)
	* ~~semincolon~~ is the Prolog OR and used in a query it returns the next instance so presumably as queries get longer the OR and AND will become more important		* Semincolon is the Prolog OR and used in a query it returns the next instance so presumably as queries get longer the OR and AND will become more important
	* ~~all~~ of the time there are more items (instances) to show the prompt does not show it only allows the next part of the query to be entered		* All of the time there are more items (instances) to show the prompt does not show it only allows the next part of the query to be entered.

			The very next item in the book is about AND and is
			loves(marsellus,X), woman(X).
			In this query we ask it to return instances that have loves(marcellas), (AND) woman (so marsellus's woman) although there are 3 instances of woman there is only one instance of marsellus and that instance happens to have a woman in this case mia so mia is the one and only return value in X

Wikisailor: /* Some learning resources */

2025-05-21T18:11:19Z

Some learning resources

← Older revision		Revision as of 18:11, 21 May 2025
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	==Some learning resources==		==Some learning resources==

	A quick search with google returned https://book.simply-logical.space/src/simply-logical.html and another site https://lpn.swi-prolog.org/lpnpage.php?pageid=top .		A quick search with google returned https://book.simply-logical.space/src/simply-logical.html and another site https://lpn.swi-prolog.org/lpnpage.php?pageid=top Both of these appear to be quite old, probably late 90s. hopefully they will give a good enough background to get me started.

			==General Concept==

			The concept of Prolog is that it is rules based rather than the more common procedural based languages like C. The focus is more on defining the problem as opposed to defining a solution by creating rule and facts to form a knowledge base


			==Introduction to Prolog==

			In one of the books in the intro pages it talks about setting up a list of fact in a Knowledgebase or KB
			woman(mia).
			woman(jody).
			woman(yolanda).
			playsAirGuitar(jody).
			party.
			What it does not say is that if I want to run that on my own computer it will not work because I would have to either write it in a text file or enter consult(user). SWI Prolog the changes the prompt to \|: (pipe colon) with ctrl to exit, so I then type in the five facts and press ctrl + d it will then return me to the ?- prompt so I can then ask the questions like
			?- playsAirGuitar(mia).
			It should return true. To be fair the simply-logical book at the first website has an interactive widget on the page and it does not need to enter the consult mode. It does not expicitly say that the termination character is the dot

			The second example also had a bit of difficulty (for me) in that I didn't see the <space> between the :- and the next part.
			consult(user). # you need this line if using a linux shell

			happy(yolanda).
			listens2Music(mia).
			listens2Music(yolanda):- happy(yolanda).
			playsAirGuitar(mia):- listens2Music(mia).
			playsAirGuitar(yolanda):- listens2Music(yolanda).

			The first two are simple facts but the third is a rule that states if happy(yolander) listen2Music(yolander) is true so the second part is the condition and the first part is the true result. This concept of making listen2Music(yolander) true if Happy(yolander) simply-logical book calls modus ponens.
			The book goes on to say that one modus ponens can be chained together with another so if we ask playsAirGuitar(yolander). it should result in true because the first fact says happy yolander and the first rule (third line) says if yolander is happy she listens2Music and finally on the 5th line it says if she listens2music yolander playsAirGuitar. As is pointed in the book out this is not explicitly stated but it is deduced from the previous facts. This demonstrates that a result of a rule can become the fact of any following rule.
			The simply-logical book states that the KBs like happy(yolander). is a predicate and that the facts and rules are called clauses. the happy(yoalder) and listen2Music(mia) are Predicates defined with one clause and listens2Music(yolanda):- happy(yolanda). is a a predicate with two clauses.

			The next example in simply simply-logical
			consult(user). # you need this line if using a linux shell

			happy(vincent).
			listens2Music(butch).
			playsAirGuitar(vincent):-
			listens2Music(vincent),
			happy(vincent).
			playsAirGuitar(butch):-
			happy(butch).
			playsAirGuitar(butch):-
			listens2Music(butch).
			Note from these examples that a statement is terminated by a dot but it can have extra clauses if separated by a comma the comma appears to be similar to an and. In the set above if vincent lists2Music AND is happy vincent playsAirGuitar. The book adds as an incidental that the formatting does not have to be like that it could be

			playsAirGuitar(vincent):-
			listens2Music(vincent),happy(vincent).
			or
			playsAirGuitar(vincent):- listens2Music(vincent),happy(vincent).
			So that is how we do an AND in prologue to do an or we would simply have two predicates as above we do with butch on the last two statements butch playsAirGuitar if happy or listens2Music. However, it would seem that we can replace the two statements for a single if using a semicolon as
			playsAirGuitar(butch):-
			happy(butch);
			listens2Music(butch).
			The book states that it would be more efficient as it is a single rule but harder to read, I would guess that would depend on the reader and if the writer was consistent with formatting.
			The next part of the book sets out some simple predicates and note there is no space between the loves predicates
			consult(user). # you need this line if using a linux shell

			woman(mia).
			woman(jody).
			woman(yolanda).
			loves(vincent,mia).
			loves(marsellus,mia).
			loves(pumpkin,honey_bunny).
			loves(honey_bunny,pumpkin).
			What the book describes using theses latest predicates is the use of variables. variables seem a bit different in Prolog than in other languages (at least to me). We can do a querry that could have more than one result like
			woman(X).
			This will retrun the first instance of woman but unlike previous it shows it without returning us to the ?- prompt
			X = mia
			If we now add space semincolon it returns the next instance and it still doesn't return us to the ?-. The third and final woman is shown we press semicolon one more time but as it is the last result from the query so as soon as it is output the ?- is displayed. There a few things to note here.
			* Variables in Prolog are anything starting with an upper case letter (which would explain why playAirGuitar and the others have a lower case first letter but the Air and Guitar both had upper case)
			* semincolon is the Prolog OR and used in a query it returns the next instance so presumably as queries get longer the OR and AND will become more important
			* all of the time there are more items (instances) to show the prompt does not show it only allows the next part of the query to be entered

Wikisailor: /* Some learning resources */

2025-05-21T14:16:18Z

Some learning resources

← Older revision		Revision as of 14:16, 21 May 2025
Line 19:		Line 19:
	==Some learning resources==		==Some learning resources==

	A quick search with google returned https://book.simply-logical.space/src/simply-logical.html and another site [https://lpn.swi-prolog.org/lpnpage.php?pageid=top].		A quick search with google returned https://book.simply-logical.space/src/simply-logical.html and another site https://lpn.swi-prolog.org/lpnpage.php?pageid=top .

Wikisailor: /* Some learning resources */

2025-05-21T14:15:57Z

Some learning resources

← Older revision		Revision as of 14:15, 21 May 2025
Line 19:		Line 19:
	==Some learning resources==		==Some learning resources==

	A quick search with google returned [https://book.simply-logical.space/src/simply-logical.html] and another site [https://lpn.swi-prolog.org/lpnpage.php?pageid=top].		A quick search with google returned https://book.simply-logical.space/src/simply-logical.html and another site [https://lpn.swi-prolog.org/lpnpage.php?pageid=top].

Wikisailor at 14:15, 21 May 2025

2025-05-21T14:15:30Z

← Older revision		Revision as of 14:15, 21 May 2025
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	The main use for Prolog will be to use it as the AI engine for the '''[[Image Processing Application]]'''. There may be other applications but that is one that will get things moving. It is assumed that it will take some time to learn how to use it with enough skill so starting now is a good idea. We will be using SWI Prolog.		The main use for Prolog will be to use it as the AI engine for the '''[[Image Processing Application]]'''. There may be other applications but that is one that will get things moving. It is assumed that it will take some time to learn how to use it with enough skill so starting now is a good idea. We will be using SWI Prolog.

			==Installation==

			To install SWI-Prolog on Ubuntu, the most common and recommended method is to use its Personal Package Archive (PPA). This ensures you get the latest stable version. You might be prompted to press Enter to confirm adding the repository.
			sudo add-apt-repository ppa:swi-prolog/stable
			After adding the PPA, you need to update your system's package information so it knows about the new packages available from the PPA:
			sudo apt update
			Now you can install the swi-prolog package:
			sudo apt install swi-prolog
			It is possible that there will be other sources but this is probably the most up to date. To prove that it is installed and working type
			swipl
			There should be some welcome message as the interactive interpreter try
			write('Hello, Prolog!').
			The interpreter should return the message Hello, Prolog! followed by true

			==Some learning resources==

			A quick search with google returned [https://book.simply-logical.space/src/simply-logical.html] and another site [https://lpn.swi-prolog.org/lpnpage.php?pageid=top].

Wikisailor: Created page with "==Introduction== The main use for Prolog will be to use it as the AI engine for the '''Image Processing Application'''. There may be other applications but that is one that will get things moving. It is assumed that it will take some time to learn how to use it with enough skill so starting now is a good idea. We will be using SWI Prolog."

2025-05-21T13:59:23Z

Created page with "==Introduction== The main use for Prolog will be to use it as the AI engine for the '''Image Processing Application'''. There may be other applications but that is one that will get things moving. It is assumed that it will take some time to learn how to use it with enough skill so starting now is a good idea. We will be using SWI Prolog."

New page

==Introduction==

The main use for Prolog will be to use it as the AI engine for the '''[[Image Processing Application]]'''. There may be other applications but that is one that will get things moving. It is assumed that it will take some time to learn how to use it with enough skill so starting now is a good idea. We will be using SWI Prolog.