CS 121 - Spring 2019

The goal of this course is for us to think in ways that are logical, organized and precise. We begin by considering the problem-solving procedure. In other words, the design and implementation of solutions. What is a programming language: what elements to we expect to find to help us write programs?

If you have your own computer, I recommend that you download Anaconda, which is a suite of software that includes Spyder, the system we will use for composing and running Python programs in this course.

There are two versions of the Python language: Python 2 and Python 3. Throughout this course we will use only Python 3. The two versions are not compatible, so please make sure you are running version 3.

Let's look at some very simple computer programs. What do you notice about them?

The purpose of this lab is to learn how to use the Spyder environment. We will run some short Python programs, and look at mathematical operators in Python.

Here are the notes for the unit on basic I/O and calculations. You should read through page 7 for Wednesday's class, and page 11 for Friday's class.

Coding conventions (identifiers, comments, indenting, blank lines)
Practice reading input of numbers and text.
Formatted output, to make our output look nice.
Variables, types, expressions
Operators including /, //, % and **
Constructor functions to change a variable's type

Example programs: Calculating win/loss record; how long to fill a swimming pool.

Let's practice a slightly longer program featuring input, basic calculations, and formatted output.

Be ready to answer the practice questions on page 5 and 6. The if statement, the 6 relational operators, using the words "and" and "or".
Also take note that we need to indent the body of an if statement.

Here is your first homework assignment, due 1/31.

We begin with while loops. Study the procedure for determining if a number is prime.

Let's practice the if statement and the while loop.

Error checking of input: uses a while loop and a boolean variable

For-loops

Be ready to finish the problems on pp. 9-11 of the loop handout.

Here is your second homework assignment, due 2/8.

Nested loops

Practice the for loop

Break and continue

Here are the notes for the unit on strings.

Begin our study of strings.

Here is your third homework assignment, due Monday 2/18.

Here are some review questions for Friday's test.
I didn't write solutions to the questions, but I would be happy to help you during office hours if you would like to go over your answers, or if you are stuck on any question.

Practice with strings.

Here are the notes for the unit on lists.

Let's begin looking at lists in Python. If you know about strings, then a lot of what we do with lists will sound familiar to you.

Lists of numbers.

Here is your fourth homework assignment, due 3/1.

The new topic this week is File I/O and Exception Handling. Here is the handout on the new unit.

Here is the handout containing notes on dictionaries, tuples and sets.

Here is your fifth homework assignment, due Friday 3/15, a short program called "warp speed".

The files you need for the lab are here.

Here is the class handout on functions, containing many examples and practice problems that we will work on during the week.

Here is your sixth homework assignment, due on 3/25. An example input file that you can test your program on is example2.txt.

Here is the lab handout.

Here are some review questions for test 2.

Here are the files you need for lab.

• Elements of the Python language.
• Writing algorithms to solve a problem.
• Turning an algorithm into a working program at the computer.
• Using pre-defined functions in Python's run-time library.

Here are some practice problems we will discuss this week.

The files you need for the lab are here.

Here is your seventh homework assignment, due 4/12.

Today in class, get into teams of 2 or 3 people. Select one of the problems to solve. You just need to explain your algorithm in English. On Friday you will present your solutions.

Here is your eighth homework assignment, due Tuesday 4/23.

Here is your ninth homework assignment, due Tuesday 4/30.

Here is the mystery code handout.

The files you need for lab are here.

During the last 10 minutes of class, you will be asked to fill out a survey about how you feel about your programming knowledge. This survey will help the CS department in our future course planning.

Here are some review questions. Please look over all your previous handouts in the course for additional practice.

This is also the last day I can accept late submissions of homework #9. It's based on my own deadline to turn in grades.