Python - Designing Algorithms(numbers, average)

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 Yosemite - 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 12(Designing Algorithms)、12.4(Exercises) 3-a, b.を解いてみる。

12.4(Exercises) 3-a, b.

コード(BBEdit)

sample3.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

def hopedaleAverage(filename):
    i = 0
    result = 0
    with open(filename) as f:
        f.readline()
        line = f.readline()
        for line in f:
            if line.startswith('#'):
                continue
            line = line.strip()
            result += int(line)
            i += 1
    return result / i

if __name__ == '__main__':
    print(hopedaleAverage('hopedale.txt'))

入出力結果(Terminal, IPython)

$ cat hopedale.txt
Coloured fox fur production, HOPEDALE, Labrador, 1834-1842
#Source: C. Elton (1942) "Voles, Mice and Lemmings", Oxford Univ. Press
#Table 17, p.265--266
      22
      29
       2
      16
      12
      35
       8
      83
     166
$ ./sample3.py
41.44444444444444
$