Animation in Python

matplotlib has a package animation that can be used directly, see for example http://matplotlib.org/examples/animation/dynamic_image2.html or this blog post.

Nicer webpage animations (within IPython notebooks or as stand-alone movies) can be created using the package JSAnimation created by Jake Vanderplas. For an example see this rendered example or Lab 15: Tuesday May 20, 2014.

Installing JSAnimation

First clone it from Github:

$ cd $HOME
$ git clone https://github.com/jakevdp/JSAnimation.git
$ cd JSAnimation

On your own laptop or the VM, you can probably install it via:

$ python setup.py install

On SageMathCloud you don’t have access to the system folder where it normally installs Python packages, but you can install it for use in one project only via:

$ sage -python setup.py install --user

Then you should be able to open Python or IPython and import JSAnimation

Alternative to installing

Rather than installing it as a package, you can just add the JSAnimation directory to the Python search path. For running it from scripts in a bash shell, you might want to add this line to your Or you can just add $HOME/JSAnimation to your PYTHONPATH environment variable:

$ export PYTHONPATH=$PYTHONPATH:$HOME/JSAnimation

This appends the path to the end of whatever path is already specified in this environment variable.

As a last resort, you can also modify the path from within a Python session:

>>> import os, sys
>>> HOME = os.environ['HOME']
>>> JSAnimation_path = os.path.join(HOME, 'JSAnimation')
>>> sys.path.append(JSAnimation_path)

JSAnimation_frametools

For animations of complex plots, it is sometimes easier to simply create the plot for each frame as usual using matplotlib and then save a .png file for each frame. These can be created and then combined to create an animation using some tools in JSAnimation_frametools.py, currently found in Lab 15: Tuesday May 20, 2014 along with some demos.

Matplotlib issues

JSAnimation requires a recent version of matplotlib. (In particular, older Ubuntu versions may not have a recent version.) If you’re having problems with matplotlib in this context, you might want to try using the Anaconda Python distribution, or switch to Using SageMathCloud.