Abdul Rahim Ahmad MITM 613 Intelligent System Chapter 10: Tools

Chapter Ten: AI Tools Abdul Rahim Ahmad A range of intelligent systems tools 10.2 Expert system shells 10.3 Toolkits and libraries 10.4 Artificial intelligence languages Lists Other data types Programming environments 10.5 Lisp Background Lisp functions A worked example 10.6 Prolog Background A worked example Backtracking in Prolog 10.7 Comparison of AI languages

Intelligent System Tools Tools to assist in constructing intelligent systems can be divided into:  Stand-alone packages, e.g., expert system shells and neural network packages;  KBS toolkits, e.g., Goldworks, Kappa, and Flex;  libraries, e.g., neural network libraries for MatLab and C++;  AI programming languages for processing words, symbols, and relations, e.g., Lisp and Prolog;  Object-oriented programming languages, e.g., Smalltalk, C++, CLOS, and Java;  Conventional programming languages, e.g., C, Pascal, and Fortran. Abdul Rahim Ahmad 3

Expert System Shell  An expert system without the knowledge base.  Consists of :  inference engine  user interface for programming  editor for creating rules  debugging tools.  user interface for running the system.  useful for building prototype expert systems but inflexible facilities for knowledge representation and inference. Abdul Rahim Ahmad 4

Toolkits  Provide knowledge representation facilities  Rules  objects or frames  uncertainty handling.  Use underlying programming language.  Need more processing power and memory  Based on the AI languages.  Goldworks is based on Lisp  Flex are based Prolog.  Kappa based on the C or C++ languages. Abdul Rahim Ahmad 5

Libraries  Similar advantages to toolkits.  Provide specific functionality within a programming environment.  Many KBS and computational intelligence libraries available, for C++, MatLab and Java. Abdul Rahim Ahmad 6

Artificial intelligence languages  Two main AI languages  Lisp  Prolog.  Both can manipulate symbolic data (characters and words), numerical data and lists. Abdul Rahim Ahmad 7

Lists  Data structures that allow words, numbers, and symbols to be combined in a wide variety of ways.  Useful for symbol manipulation  A feature of Lisp and Prolog.  Example of Lisp or Prolog, respectively, as follows: Abdul Rahim Ahmad 8 LISP (close_valve (exceeds pressure 10 mpa)) PROLOG [if, pressure, exceeds, 10, MPa, then, close, valve]

C++ vs LISP vs PROLOG Abdul Rahim Ahmad 9 LISP (close_valve (exceeds pressure 10 mpa)) PROLOG [if, pressure, exceeds, 10, MPa, then, close, valve] To represent a simple fact such as: pressure in valve #2 is 12.8 MPa C++

Comparison of AI Languages PROLOG  Prolog code is the most compact and elegant solution to the problem of choosing materials which meet a specification  Because Prolog is good at tasks that involve pattern matching and retrieval of data.  Many constraints on the programmer, particularly in committing him or her to one particular search strategy.  Prolog doesn’t need a structure for iteration, e.g., FOR x FROM 1 TO 10, as recursion can be used to achieve the same effect.. Abdul Rahim Ahmad 10 LISP  Lisp has a completely different structure from Prolog  Procedural (or functional) language.  Good in manipulating symbols and lists of symbols.  Allows practically any reasoning strategy to be implemented. In fact, it is so flexible that it can be reconfigured by the programmer.