Symbolic AI www.cems.uwe.ac.uk/~ryang/prolog/top.html

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Symbolic AI www.cems.uwe.ac.uk/ryang/prolog/top.
html

• weeks of even numbers
• Lecture
• Monday 1300-1400 (2Q50)
• Lab Sessions (five groups, all in 2Q52)
• Monday 1400 , 1500
• Tuesday 1100, 1500 , 1600

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Assessment Method

• Coursework 40 (Coding in Prolog)
• Examination 60 (4-5 questions in AI
• 1 question in Prolog)
• How to Pass the coursework
• Dont miss lectures, and always finish practical
  work on time.

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A Preliminary Plan for this Term

• Lecture 1 Introduction, Logic Formulas, Logical
  Inferences
• Lecture 2 Syntax and Semantics of Prolog
• Lecture 3 Unification, Proof Tree
• Lecture 4 Lists, Recursions
• Lecture 5 More on Lists, Some Prolog Built-ins
• Lecture 6 A Case Study
• Lecture 7 Modifying Programs Dynamically/Controll
  ing Backtracking
• Lecture 8 Natural Language processing
• Lecture 9 Input and Output
• Closed World Assumption
• Lecture 11 Comparing with Others Languages
• Lecture 12 Revision
• (out of date, be aware of changing)

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Books

• Prolog Programming by Paul Brna
• (a free copy available for everyone)
• Logic Programming and Prolog by Ulf Nilsson and
  Jan Matuszynski
• Prolog Programming for AI by Ivan Bratko

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Programming Languages

• Imperative
• Procedure oriented
• C, Fortran
• Object oriented
• C, Java

• Declarative
• Functional langauge
• Haskell
• Logic language
• Prolog
• (PROgramming in LOGic)

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Background - Logic

• Logic a tool for reasoning
• Logical formulas
• a formal way to describe things
• Logical Operators and , or , not , imply
  

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Logical Formulas

• Examples
• Mary loves Tom gt
• Every mother loves
• her children gt

• loves(mary, tom)
• VX VY(loves(X,Y) lt-
• mother_of(X,Y))

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Logical Formulas (more examples)using
boy_names(Name, Year, Pos)

• The most popular boys name in 1800 is John.
• The second popular boys name in 1800 is Thomas.
• A popular boys name within a year means that
  the name is listed in the top 50 list. ( -
  means lt- )

• boy_names(
• john, 1800, 1).
• boy_names(
• thomas, 1800, 2).
• pop_boy_names(X,Year)
• -
• boy_names(X,Year,P),
• P lt 50.

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A Famous Equation

• Algorithm Logic control
• (by Rob Kowalski )
• Example
• What is the length of a list?
• Find who is Freds grandparents

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Imperative Languages Prolog
programmer has to express control sequence explicitly control is built into the system
data and program have different structure data and program have same structure
program can't change itself as it runs program can be changed as it runs
variable a memory store / destructive assignment variable logical variable single assignment