Python - Designing and Using Functions(absolute value(built-in function, abs))

Practical Programming
An Introduction to Computer Science
Using Python 3
(Pragmatic Programmers)
(Pragmatic Bookshelf)
Paul Gries (著) Jennifer Campbell (著)
Jason Montojo (著) Lynn Beighley (編集)

開発環境

• OS X Mavericks - Apple(OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python 3.4 (プログラミング言語)

Practical Programming: An Introduction to Computer Science Using Python 3 (Pragmatic Programmers) (Paul Gries (著)、Jennifer Campbell (著)、Jason Montojo (著)、Lynn Beighley (編集)、Pragmatic Bookshelf)のChapter 3(Designing and Using Functions)、3.11-4.を解いてみる。

3.11-4.

コード(BBEdit)

入出力結果(Terminal, IPython)

$ ipython
Python 3.4.1 (default, May 21 2014, 01:39:38) 
Type "copyright", "credits" or "license" for more information.

IPython 2.1.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

In [1]: def difference(a, b):
   ...: return abs(a - b)
   ...: 

In [2]: difference(5, 10)
Out[2]: 5

In [3]: difference(10, 5)
Out[3]: 5

In [4]: difference(-5, 5)
Out[4]: 10

In [5]: difference(5, -5)
Out[5]: 10

In [6]: quit()
$