CS21B — Intro to Comp Sci: Apps in Bio
Spring 2010

Schedule | Lab Sessions | Study Sessions | Succeeding | Grading


The final exam is scheduled for Wednesday, May 12th, 7-10pm in SCI 101.

Class Information

Room: Science Center 252
Class: Tuesday, Thursday 9:55–11:10pm
Professor: Lisa Meeden
Office: Science Center 243
Phone: 8565
Office hours: I will be available Wednesdays 2-4pm, or you can stop by whenever my door is open.

Welcome to CS21B. This course will introduce fundamental ideas in computer science and teach you how to write computer programs while exposing you to some applications in biology. We will study algorithms for solving problems and implement solutions in the Python programming language. Python is an interpreted language that is known for its ease of use. We also introduce object-oriented programming and data structures. A deeper coverage of these topics will be presented in CS 35.

This course is appropriate for all students who want to learn how to write computer programs and think like computer scientists. It is the usual first course for computer science majors and minors. Students with advanced placement credit or extensive programming experience should place out of this course and instead begin with CS 33 or CS 35.

Required Textbook

Goals for the course

By the end of the course, we hope that you will have developed the following skills:

Student Support

Student Support Coordinator: Betsy Horner (Office: Science Center 257, Phone: 6062)

CS21 Ninjas (student mentors): John Dinh, Christina Duron, Ivana Ng, Ashley Oudenne, Nick Rhinehart

Study sessions

The CS Ninjas will assist me in class and run study sessions in the main CS lab (Science Center 240) on the following evenings:

Day Time Location
Sunday 7-9pm Sci Center 240
Wednesday 7-9pm Sci Center 240

You are invited -- and encouraged -- to participate in these study sessions to prepare for quizzes, to discuss programming concepts, and to get friendly assistance in working on homework assignments. Our CS mentoring team is dedicated to helping students, who have no prior knowledge of computer science, learn to program in Python while keeping their senses of humor intact. As an added bonus, free food will be provided at the sessions.

Lab Sessions

The CS lab is open 24 hours a day, 7 days a week for you to use for CS21 lab assignments. In addition, the CS21 professors will be in the CS labs at the times listed below to help CS21 students with lab assignments. You are not required to attend any of these sessions, but you should take advantage of them to get assistance with your lab assignments. Any CS21 student is welcome to attend any/all session.

Day Time Professor Location
Monday 2:30-4:00 Newhall Science Center 240
Monday 3:30-5:00 Meeden Science Center 240
Friday 1:00-2:00* Turnbull Science Center 240
* If there's a campus collection, the Friday lab will be 2-3pm in the overflow lab.

Accessing the CS labs after hours

You can use your ID to gain access to the computer labs at nights and on the weekends. Just wave your ID over the microprox reader next to the lab doors. When the green light goes on, just push on the door handle to get in (the door knob will not turn). If the green light doesn't go on, then we need to enter your microprox number into the system. email local-staff@cs.swarthmore.edu if you have problems with this. If the building is locked, you can use your ID to enter the door between Martin and Cornell library. For this class, your ID will give you access to the labs in rooms 238 and 240.

How to Succeed in CS 21

Academic Accommodations

Academic accommodations are available for students with disabilities who are registered with Student Disability Services in the Dean's office. Students in need of disability accommodations should schedule an appointment with me early in the semester to discuss accommodations for this course that have been approved by the Dean's office. All requests must come through an accommodation letter from the Dean's office. To receive an accommodation for a course activity, your meeting with me must be at least one week prior to the activity.

Contact Tracey Rush at the Dean's office and follow these steps for obtaining accommodations.


Grades will be weighted as follows:
40%Homework assignments
5%Class Participation
25%Final Exam

Homework policy

Programming assignments will typically be assigned in class at the beginning of the week and will be due before midnight the following Tuesday night. You are strongly encouraged to start early and to attend the study sessions for extra practice.

You will submit you assignments electronically using the handin21 program. You may submit your assignment multiple times, but each submission overwrites the previous one and only the final submission will be graded. Late assignments will not be accepted except in extreme situations and only if you contact me before the deadline. Even if you do not fully complete an assignment, you should submit what you have done to receive partial credit.

Programming Style

Programming is not a dry mechanical process, but a form of art. Well written code has an aesthetic appeal while poor form can make other programmers and instructors cringe. Programming assignments will be graded based on style and correctness. Good programming practices usually include many of the following principles:

Academic Integrity

Academic honesty is required in all work you submit to be graded. With the exception of your lab partner on lab assignments, you may not submit work done with (or by) someone else, or examine or use work done by others to complete your own work. Your code should never be shared with anyone; you may not examine or use code belonging to someone else, nor may you let anyone else look at or make a copy of your code. This includes sharing solutions after the due date of the assignment.

All code you submit must be your own with the following permissible exceptions: code distributed in class, code found in the course text book, and code worked on with an assigned partner. In these cases, you should always include detailed comments that indicates on which parts of the assignment you received help, and what your sources were.

Discussing ideas and approaches to problems with others on a general level is fine (in fact, we encourage you to discuss general strategies with each other), but you should never read anyone else's code or let anyone else read your code. You may discuss assignment specifications and requirements with others in the class to be sure you understand the problem. In addition, you are allowed to work with others to help learn the course material. However, with the exception of your lab partner, you may not work with others on your assignments in any capacity.

``It is the opinion of the faculty that for an intentional first offense, failure in the course is normally appropriate. Suspension for a semester or deprivation of the degree in that year may also be appropriate when warranted by the seriousness of the offense.'' - Swarthmore College Bulletin (2008-2009, Section 7.1.2)

Please see me if there are any questions about what is permissible.


1 Jan 19   Introduction to Python and Unix
Zelle chapters 1-2
Jan 21  
2 Jan 26   Numbers and Strings
Zelle chapters 3-4
Jan 28 Quiz 1
Practice Quiz1
Drop/Add ends (Jan 29)
3 Feb 02   Booleans
Zelle chapter 7 and pg. 247
Feb 04  
4 Feb 09   Graphics, Objects
Zelle chapter 5
Notes on the Graphics Library
Feb 11 Quiz 2
Practice Quiz2
5 Feb 16   Functions, Objects
Zelle chapter 6
Feb 18  
6 Feb 23   while Loops, More Functions
Zelle chapter 8
Feb 25 Quiz 3
Practice Quiz3
7 Mar 02   Top Down Design, File I/O
Zelle chapter 9, section 4.6
Mar 04  

Mar 09

Spring Break

Mar 11

8 Mar 16   Searching, Analysis of Algorithms
Zelle section 13.1
Mar 18  
9 Mar 23   Sorting, Analysis of Algorithms
Zelle sections 13.2-13.3
Mar 25 Quiz 4
Practice Quiz4
Last day to declare CR/NC or W (Mar 26)
10 Mar 30   Recursion
Zelle sections 13.1-13.3
Apr 01  
11 Apr 06   Defining new classes
Zelle chapter 10
Apr 08 Quiz 5
Practice Quiz5
12 Apr 13   Object Oriented Design
Zelle chapter 12
Apr 15  
13 Apr 20   Linked lists
Apr 22 Quiz 6
Practice Quiz6
14 Apr 27   Advanced Topics, Wrap-up
Apr 29