Your First Program in Python on Linux


This page tells you how to setup a Python programming environment for your Linux computer and provides a step-by-step guide for creating and running a simple "Hello, world" Python program. All of the software is freely available on the Web.



Overview

The Python programming environment required by this booksite consists of:

At the time of writing, some parts of the Pygame library still have not been ported to Python 3. So the instructions that follow are for Python 2, not Python 3.



Downloading and Installing Python, Tkinter, NumPy, Pygame, and setuptools

Using your package manager (for example, Synaptics), download and install these packages: python, python-tk, python-numpy, python-pygame, and python-setuptools. The package names may vary slightly across Linux distributions.

Perform these steps to test your installations:



Downloading and Installing the Booksite Library

Perform these steps to download and install the booksite library:

Perform these steps to test your installation of the booksite library:



Configuring IDLE

So far you've downloaded and installed all of the software that you'll need. You should perform one more step before creating your first program: configure the IDLE programming environment. Follow these instructions:



Composing Your First Program

Having installed Python, the Python standard libraries, IDLE, Tkinter, NumPy, Pygame, and the booksite libraries, and having configured IDLE, you are ready to compose your first Python program. Perform these instructions:



Running Your First Program

The final step is to run your program. It is possible to run some Python programs from within IDLE, but you should run the programs associated with this booksite directly from a terminal window. To do that, perform these steps:

You now have installed and configured a reasonable Python environment, and have used it to compose and run a Python program. Congratulations! You are a Python programmer!



Downloading the Booksite Example Programs (optional)

We recommend that you download the booksite example programs, that is, the example Python programs that are presented incrementally throughout the booksite. Having done so, you can run those programs to help you learn about them. Perform these instructions:

Then perform these steps to test your download of the booksite example programs:



Downloading the Booksite Example Data (optional)

We recommend that you download the booksite example data, that is, the data files used by the booksite example programs that are presented incrementally throughout the booksite. Perform these instructions:



Downloading the Booksite Library: Part 2 (optional)

Previously on this page we described how to download and install the booksite library so Python can find it. Now we describe how to download the booksite library so you can find it — for the sake of studying the code that implements it, should you so desire. Perform these instructions:

We invite you to study the code that implements the booksite library. But don't be concerned if some of the code is cryptic. The code that implements the booksite library uses some features of Python that are beyond the scope of the textbook and this booksite.



Q & A

Q. My Linux distribution doesn't come with a package manager. Can I install the required software without one?

A.Yes, but the procedure for doing so depends upon which Linux distribution you're using.

With DEB-based distributions (Debian, Ubuntu, etc.), you typically would use the apt-get command to download and install specified .deb files. The more primitive alternative is to download the .deb files using some other mechanism, and then install them using the dpkg command.

With RPM-based distributions (Red Hat, Fedora, CentOS, SUSE, etc.), you typically would use the yum command to download and install specified .rpm files. The more primitive alternative is to download the .rpm files using some other mechanism, and then install them using the rpm command.

With Ebuild-based distributions (Gentoo, etc.), you typically would use the emerge command to download source code.

Q. How do I break out of an infinite loop when running my program from the terminal?

A. Type Ctrl-c. That is, while pressing the Ctrl key, type the c key.

Q. I downloaded files using my browser, but can't find them. Where are they?

A. Many browsers by default place downloaded files in the directory /home/yourusername/Downloads.

Q. Must I use IDLE to create my Python programs? Can I use some other text editor?

A. You need not use IDLE to create your Python programs; it is fine to use some other text editor. However if you do use some other text editor, then make sure you change its settings so it (1) uses a four-space indentation scheme, and (2) indents using spaces instead of tabs. The Wikipedia Comparison of text editors page provides summary descriptions of many text editors.