Python - Math - Visualizing Data with Graphs(Visualizing Your Expenses)

Doing Math with Python
(No Starch Press)
Amit Saha (著)

開発環境

• OS X El Capitan - Apple (OS)
• Emacs (Text Editor)
• Python 3.5 (プログラミング言語)

Doing Math with Python: Use Programming to Explore Algebra, Statistics, Calculus, and More! (Amit Saha (著)、No Starch Press)のChapter 2.(Visualizing Data with Graphs)、Programming Challenges #4: Visualizing Your Expenses(No. 1472)を解いてみる。

#4: Visualizing Your Expenses(No. 1438)

コード(Emacs)

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

import matplotlib.pyplot as plt

def create_bar_char(data, labels):
    plt.title('Weekly expenditures')

    num_bars = len(data)
    positions = range(1, num_bars + 1)
    plt.barh(positions, data, align='center')
    plt.yticks(positions, labels)
    plt.xlabel('Amount')
    plt.ylabel('Categories')
    plt.grid()
    plt.savefig('weekly_expenditures.svg')
    plt.show()

if __name__ == '__main__':
    try:
        categories = []
        expenditures = []
        num = int(input('Enter the number of categories: '))
        for _ in range(num):
            category = input('Enter category: ')
            expenditure = int(input('Expenditure; '))
            categories.append(category)
            expenditures.append(expenditure)
            print()
    except Exception as err:
        print(err)
    else:
        create_bar_char(expenditures, categories)

入出力結果(Terminal, IPython)

$ ./sample4.py
Enter the number of categories: 4
Enter category: Food
Expenditure; 70

Enter category: Transportation
Expenditure; 35

Enter category: Entertainment
Expenditure; 30

Enter category: Phone/Internet
Expenditure; 30

$