Concepts of Programming Languages Qassim University

1. Prolog Programming Language
CSE 337
Concepts of Programming Languages
Qassim University
College of Computer –IT department
Ms.Sadaf Ambreen Abbasi.
Reham AL blihed
Muna AL rajhi
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2. Outline
• About Prolog programming language
• Simple idea of prolog program
• Prolog Syntax
• General purpose arithmetic
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3. About prolog programming language
•Prolog
• Prolog is one of the most widely used programming languages in artificial
intelligence research.
• It is a declarative programming language unlike most common programming
languages.
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4. Simple Idea about Prolog Program
• Prolog programs specify relationships among objects and
properties of objects.
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PrologEnglish
father(ibrahim,reham).Ibrahim is the father of Reham.
eats(ibrahim,pizza).Ibrahim eats pizza.
happy(muna).Muna is happy.

5. Prolog Syntax
• Terms
• Terms are of four kinds: atoms, numbers, variables, and compound terms.
• Example atom:
• Example variables:
• Example compound term:
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elephant, b, abcXYZ, x_123
X, Elephant, _
is_bigger(horse, X), f(g(X, _), 7),

6. Prolog Syntax
• Clauses and Queries
Clauses Facts & Rules
A fact is a predicate followed by a full stop.
Example:
A rule consists of a head and a body .Head and body are separated by the sign :-
Example:
Queries
it is a sequence of predicates separated by commas and terminated by a full stop.
Example:
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bigger(whale, _).
Head :- Body.
is_smaller(X, Y) :- is_bigger(Y, X).
aunt(Aunt, Child) :-
sister(Aunt, Parent),
parent(Parent, Child).
?- weather(City,summer), temp(City,40).

7. General Purpose Arithmetic
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• Numeric comparison operator:

8. General purpose arithmetic
• The is-Operator for Arithmetic Evaluation
• The expression in the right of the is-Operator is evaluated and bound to
the left hand argument.
• = does not cause evaluation of its arguments:
• Example:
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9. Lists in Prolog Programming language
• List contain of head and tail and separated by bar sign | (bar).
• Example:
• Example:
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10. Some Built-in Predicates for List Manipulation:
• Length
• Sum
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11. General Example of prolog
• personal Information
• Knowledge Based
• Queries
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12. General Example of prolog
Example on testing mark
• Knowledge Based
• Queries
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13. General Example of prolog
Example of prolog program about the Weather
• Knowledge Based
• Queries
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14. General Example of prolog
• Maximum of two numbers
• Knowledge Based
• Queries
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15. General Example of prolog
• Example:
Knowledge Based
Queries
• Example:
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