In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.
Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "Notice that
numpysum() does not need a
A block of code is set as follows:
def pythonsum(n): a = range(n) b = range(n) c =  for i in range(len(a)): a[i] = i ** 2 b[i] = i ** 3 c.append(a[i] + b[i]) return c
Any command-line input or output is written as follows:
$ yum install python-numpy
New terms and important words are shown in bold. Words that you see on the screen, in menus ...