Using Python in IDeATe

The example code for the course includes Python scripts, primarily for controlling hardware via a serial-attached Arduino. The following notes will guide you in getting started on running the examples on the IDeATe cluster laptops.

Python in the IDeATe MBP Cluster

The course primarily supports using the IDeATe cluster MacBook Pro laptops for Python development. However, these laptops have at least three different Python intepreters:

  • MacPorts Python (recommended): /opt/local/bin/python2.7
  • The system Python supplied by Apple: /usr/bin/python
  • An independent Python 3: /usr/local/bin/python3

The standard Python libraries are quite comprehensive but do not include several essential libraries needed for Physical Computing work (notably pySerial). For this reason, the only supported interpreter is the MacPorts installation.

An example of running a course Python script from the command line (e.g. Terminal) might look like this:

$ /opt/local/bin/python2.7 mini_maestro_dfmoco.py --help

The initial $ represents the prompt, /opt/local/bin/python2.7 the specific Python interpreter from MacPorts, mini_maestro_dfmoco.py is the particular script to run, followed by command-line arguments. In this case, --help will simply print out all possible arguments.

Python in the IDeATe Dell Cluster

The course materials have not yet been tested under Windows 10 on the IDeATe Dell cluster laptops. However, these machines have Anaconda Python 2 and 3 installed so in principle should work.

Reference: IDeATe Software.

Python Tutorials

For tutorials: https://www.python.org/about/gettingstarted/

For documentation: https://www.python.org/doc/

For information on third-party packages: https://pypi.python.org/pypi

Editing Python

Python is a whitespace-sensitive language in which indentation must be precise. This essentially requires use of a syntax-sensitive programming text editor.

For beginners, the IDLE editor is recommended. The XCode editor works with Python. Advanced command-line users may enjoy emacs or vim. Many people seem to like the commercial Sublime Text application.

A much longer list can be found at https://wiki.python.org/moin/PythonEditors

Python 2.7 vs 3.5

Python currently exists in two major branches. Python 3 introduced incompatible features, so many projects have continued to use Python 2 for better library support. The situation is slowly resolving as libraries are being ported forward.

The course materials are written in a 2/3 compatible style and tested on both Python 2.7 and 3.5. Currently, 2.7 is recommended for use on the IDeATe laptops but the transition to 3 is underway. Please note that 3.5 isn’t the latest version, but we expect newer versions to work equally well.

For more details on cross-version compatibility, please see Python-Future.

Python on your own laptop

Since we provide the cluster machines, we will not provide support for your personal systems, it is just too labor-intensive. But if you’d like to set one up, here are notes which may help.

macOS MacPorts

MacPorts is an open-source package installation system for macOS. Effective use of MacPorts requires some willingness to use the command line (e.g. Terminal.app). The MacPorts Quickstart instructions are the best reference for initial installation.

The following command line will then install all additional packages required by the course examples. Note that you may see many other packages installed by MacPorts as it automatically installs packages required by the ones you specify:

sudo port install python27 py27-future py27-serial py27-numpy py27-pyqt5 qt5-mac

If you’d prefer to use Python 3, you could also try this:

sudo port install python35 py35-future py35-serial py35-numpy py35-pyqt5

Additional recommended packages:

sudo port install py27-pip py27-virtualenv py35-pip py35-virtualenv

macOS or Windows Anaconda Python

Anaconda is a Python distribution for Windows, Mac or Linux which includes a package manager and comprehensive package system. The installer will include many third-party packages in the default installation, notably PyQt5 and numpy. We recommend it over the Python.org distribution because these third-party packages make it more immediately usable.

The course software has not yet been tested in this environment, but it likely the only additional package needed will be pySerial, available through the Anaconda Navigator or the command-line conda package manager.