Logic Programming 06-25433 Autumn 2012

Lecture 7: Processing lists in Prolog This lecture begins by revisiting the example of iteration expressed as recursion. Lists are introduced as a versatile data structure then the essentials of list processing in Prolog are demonstrated. This lecture will: explain why lists offer versatility; describe the syntax of lists in Prolog; show how Prolog unifies lists; introduce three common patterns of termination in list processing: when a certain number of list elements have been scanned; when the end of a list is reached (ald so all elements scanned); when a given element is found.

How to prepare   Revise you knowledge of basic list processing either by: revising the material in Foundations of Computer Science I; or reading the introductiory section of the Prolog WWW notes.

Video   Recording of the lecture (Vimeo)

Slides   If you really want the slides from the lecture ... 1 slide per page 6 slides per page but don't forget printing the slides is not the same as understanding them.

Summary   Summary and programs with commentary from the lecture

Programs from the lecture   Example 1 - for_loop Example 2 - length of a list Example 3 - classifying elements of a list Example 4 - membership of a list Example 5 - finding the nth member

Individual study suggestions and further reading   Topics on lists to be studied include: the unification of lists; termination criteria. List processing is covered in: Bratko. 3rd ed. Sections 3.1-3.2, pp 61-67. Clocksin & Mellish. Chapter 3, sections 3.1-3.3, pp 47-57. Covington. Chapter 3, sections 3.5-3.9, pp 69-77. Sterling & Shapiro. Chapter 3, section 3.1, pp 45-56.

Assessed work associated with this lecture   Tutorial sheet 3 Tutorial sheet 4