You learned about testing and NumPy testing utilities in this chapter. We covered unit testing, docstring tests, assert functions, and floating-point precision. Most of the NumPy assert functions take care of the complexities of floating-point numbers. We demonstrated NumPy decorators that can be used by nose. Decorators make testing easier and document the developer intention.

The topic of the next chapter is matplotlib—the Python scientific visualization and graphing open source library.