Since NumPy is a prerequisite for pandas, and you have already installed pandas, NumPy is ready to be used. All that is required to do to use NumPy is to import the library and so all that is required for the examples in this chapter and for most of this book is the following import command:

In [1]:
   # this allows us to access numpy using the
   # np. prefix
   import numpy as np

This makes the top-level functions of NumPy available in the np namespace. This is a common practice when using NumPy, and this book will follow this convention for accessing NumPy functionality.