ImportError: No module named matplotlib.pyplot

You have two pythons installed on your machine, one is the standard python that comes with Mac OSX and the second is the one you installed with ports (this is the one that has matplotlib installed in its library, the one that comes with macosx does not).

/usr/bin/python

Is the standard mac python and since it doesn't have matplotlib you should always start your script with the one installed with ports.

If python your_script.py works then change the #! to:

#!/usr/bin/env python

Or put the full path to the python interpreter that has the matplotlib installed in its library.

pip will make your life easy!

Step 1: Install pip - Check if you have pip already simply by writing pip in the python console. If you don't have pip, get a python script called get-pip.py , via here: https://pip.pypa.io/en/latest/installing.html or directly here: https://bootstrap.pypa.io/get-pip.py (You may have to use Save As ..)

Step 2: Take note of where the file got saved and cd the directory from command prompt. Run the get-pip.py script to install pip. You can write in cmd this line within quotes: "python .\get-pip.py"

Step 3: Now in cmd type: pip install matplotlib

And you should be through.