Computer Science 1300/5001
Python is an open-source programming language that is freely-available for all major computing platforms. Something to be aware of is that there are two major versions of Python currently in use (the so called Python 2.x branch and Python 3.x branch). We will be using the 3.x line in this course (and it is not backward compatible with the 2.x branch).
If you are using your account on our department's hopper
system, Python is already installed and can be started by typing the
command python3 in a console window (not to be
confused with the command python which is the default 2.x
branch). There is also a development environment for Python known as IDLE that is available by
navigating the start menu to
If you wish to run locally on your own computer, Python can be easily installed. In fact, if you have an Apple computer, Python and IDLE are already pre-installed as part of the OSX distribution. You can open a terminal window and start Python by typing the command python, or IDLE by typing the command idle. For other platforms, you can download a Python installer from www.python.org/download; make sure to download the Python 3.x line (Python 3.5.6 is the most current release as of August 2018).
While it will be helpful to have the Python interpreter installed on your own computer, there are actually many very good web-based tools that would provide you with either an interactive interpreter or even ways to execute Python scripts through a browser. Those are great both for exploring, and perhaps even for completing assignments. In the end, what you will typically be submitting for programming assignments is your source code, so if you can develop that on a web-based platform, that's okay.
Here are some sites that we can recommend:
The official Python organization's website provides an interactive interpreter on their website at https://www.python.org/shell/
There is a wonderful web site named pythontutor.com that allows you to walk through the execution of a Python program, step-by-step, while providing a helpful visualization of your current workspace.
repl.it/site/languages/python3 provides a full IDE for developing and executing Python code in the browser.
The graphics support for this class is provided by a module named cs1graphics developed here at SLU. It is not an official part of the Python distribution, so you will need to make sure to have it available on your system as well. If working on our department system, it is already available. If working on your own system, you will need to download a single file named cs1graphics.py. The most recent public release of this software is available at www.cs1graphics.org.
There are two ways to use the file on your own computer. One is to make sure to place the file in the same directory in which you are working when you start the Python interpretter. A better approach is to install the package by placing the file on your system in a folder typically named site-packages that is part of the Python distribution. If you have trouble finding the location of that package, please type the following command while within the Python interpreter.
>>> import sys; print([p for p in sys.path if 'site-packages' in p])