CS 111: Introduction to Computer Science

Working on your own computer

Among those students who own their own computers, many prefer to set up their computers with the software required for doing CS111 work. Doing this setup is an idiosyncratic business, so it's hard to give explicit step-by-step guidance that works for everyone. The CS Department tries to provide some pointers on setting up your own computer, but doesn't guarantee that we can help you make everything work. If you can't get things working on your own machine, you can always use our labs (CMC 102, 304, 306).

That said, here are a few notes that might help.

First, here's what you will need:

• A Unix command-line interface
• Python 3
• A couple Python add-ons that don't get installed automatically when you install Python 3. We'll discuss these modules when we get to them during the second half of the term.
• A text editor designed for programmers. There are many, but right now, I like Atom and Brackets, both of which are available for free. In the classroom, we will use BBEdit, because the college has a campus-wide license for it, but as an individual, you would have to pay for it.

How to install this software depends mostly on your computer's operating system. Here's a little guidance on the Unix and Python 3 installations. The text editor should be straight-forward to install, so I'll leave you on your own for that.

• On Windows 10, you can install the Windows Subsystem for Linux to get a Unix command shell (bash). Once you have it set up, it usually works great, but it can be a bit of a tricky installation process.

  I've searched around for helpful guides, and this installation guide at How-To Geek looks quite good.

  Once you have the Windows Subsystem for Linux working and you have opened a bash prompt, try executing

  python3
  If that shows you the >>> prompt, great! You're ready to go. But if it tells you "command not found" or "permission denied" or something like that, then you need to install Python 3, like so:
  sudo apt install python3
  This will ask you to type your password, but should then let you run python3 after it's done installing.

  IMPORTANT: If you use the Windows Subsystem for Linux, then I recommend the following work procedure.

  • In Windows, create a new folder called CS111 or something like that. You could put it on your Desktop or in Documents. I'm going to assume the CS111 folder is on your Desktop.
  • Save your Python files (like hello.py) in that CS111 folder. So its full name would be C:\Users\YOUR_USER_NAME\Desktop\CS111\hello.py
  • At the bash prompt, change directories so you're in that CS111 folder. To do that, you do like so:
    cd /mnt/c/Users/YOUR_USER_NAME/Desktop/CS111
    Then you can do
    python3 hello.py
    and it should work fine. That "/mnt/c" thing gives you a way of using the normal Windows folder structure from within bash. You will avoid all sorts of nasty problems if you do that.

  Getting all this set up on Windows is just harder than it is on macOS or Linux, but on the other hand, you're likely to learn lots of miscellaneous stuff about your computer while you do the setup. Learning to configure your own software development environment is undeniably a headache, but it is also empowering. Be persistent and ask for help.

• macOS is based on one of the main variants of Unix, and Macs come with the Terminal app pre-installed. So for the Unix part of your installation, you're set up without doing anything. You'll still need to install Python 3, however. For this, I strongly urge you to use Homebrew. Follow the "Install Homebrew" instructions on their homepage, and then, in Terminal, do this:
  brew install python3
  Test the result by typing "python3" in Terminal and seeing whether you get the >>> prompt.
• Linux. All distributions of Linux come with a terminal program that is usually featured pretty much front and center (maybe with a Desktop shortcut, for example). Some of them have Python 3 installed, but if "python3" doesnt give you the >>> prompt, then try this:
  apt-get install python3