I noticed a minor mistake in the documentation for _convertToTransferFunction. In particular, in the example

sys = _convertToTransferFunction([[1. 0.], [2. 3.]])

the numbers should be separated by commas. That made me wonder if there were mistakes in other examples, so I ran all of the examples as doctests with nosetests --with-doctest. That reveals 38 failed tests, and 1 error. Many of these problems are because some quantities are not defined in the examples. For instance:

T, yout = initial_response(sys, T, X0)

gives NameError: name 'sys' is not defined. I think it would be good to make these examples all self-contained and "runnable", so that 1) they are complete (e.g., users know exactly how to define an object like sys in the example above); and 2) they can be automatically tested as doctests. Any comments or objections?