Page 74 - DCAP310_INTRODUCTION_TO_ARTIFICIAL_INTELLIGENCE_AND_EXPERT_SYSTEMS

Introduction to Artificial Intelligence & Expert Systems

Notes
Example 5:

Objective: Write a program in LISP showing implementation of condition.
Solution:
Maximum of Two Numbers
:->(defun maximum2 (a b) (cond ((>a b) a) (t b)))
MAXIMUM2

OUTPUT
(maximum2 234 320)
:-> 320

Maximum of Three Numbers
(defun maximum3(a b c)(cond((>a b)(cond((>a c)a)(t c)))((>b c)b)(t c)))
MAXIMUM3
OUTPUT
(maximum3 20 30 25)

:-> 30

Task Write a LISP program for login and password checking.

Self Assessment

State whether the following statements are true or false:
13. LISP is a language that is usually associated with the Functional Programming paradigm.
14. To define a procedure we use the special operator average.
15. The words you use for the parameters are arbitrary.
16. A procedure does have to have any parameters.

4.5 Summary

LISP programs are made up of expressions, which are lists or single atoms.
Lists are made up of zero or more atoms or inner lists, separated by white space and
surrounded by parentheses. A list can be empty.
Atoms are multi-character symbols, like forward-paragraph, single character symbols
like +, strings of characters between double quotation marks, or numbers.

A number evaluates to itself.
A string between double quotes also evaluates to itself.
When you evaluate a symbol by itself, its value is returned.

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