Class 03: Python Lab

Held: Tuesday, February 2, 2010

Summary: You ground your learning of the Python programming language with some hands-on exercises.

Related Pages:

• EBoard.

Notes:

• Beautiful Code reading for Thursday: Chapter 19: Multidimensional Iterators in NumPy.
• Other reading for Thursday: Find something interesting on UML and then send me a question.
• Summer MAP discussion, today at 4:15 in JRC 101.
• EC: Thursday's CS Extra: Summer opportunities in CS.
• EC: Friday's CS Table: Pair Programming.

Overview:

• Beautiful Code 27.
• About programming exercises.
• Programming Exercise 1: Some Basics.
• Programming Exercise 2: Binary Search.
• Programming Exercise 3: A Fraction Class.

Beautiful Code 27: RESTful Programming

• Don't forget to check out the questions/comments on this reading.
• What is the application that Patzer describes?
• What is Patzer's primary thesis?
• What lessons does Patzer expect you to take from this example?
• What makes the code beautiful?
• What makes the code ugly?

Programming Exercises

• We'll do a few rounds of programming execises.
• At some point, I'll stop you and we'll go over the code you've written for one round.
  • It's okay if you're not finished by the time I stop you.
  • If you finish one round before the discussion, just go on to the next round.
• Be prepared to discuss what you had difficulty with in each round.

Round 1: Some Basics

• Write some simple program segments to make sure that you understand the core aspects of Python: Variables, Strings, Procedures, Conditionals, Lists, Loops, Classes, and Dictionaries
• Create a small inheritance heirarchy and figure out what happens when multiple ancestors provide methods with the same name.
• Write a simple grep procedure that takes as parameters a pattern string and a list of strings, and returns a list of all strings in the list that contain the pattern. (The pattern should be taken verbatim.)

Round 2: Binary Search

• Simplified problem:
  • Inputs:
    • i, an integer
    • vals, a sorted array (list) of integers. (Sorted in increasing order.)
  • Output:
    • If i is in vals, the index of i
    • If i is not in vals, -1

Round 3: A Fraction Class

• Implement a simple fraction class to represent rational numbers. Make sure to support traditional operations on rationals.