Python - Making Choices - Nested if Statements, Remembering Results of a Boolean Expression Evaluation

Practical Programming
楽天ブックス(Kobo) 紀伊国屋書店(Kinoppy)

開発環境

• macOS Mojave - Apple (OS)
• Emacs (Text Editor)
• Windows 10 Pro (OS)
• Visual Studio Code (Text Editor)
• Python 3.7 (プログラミング言語)

Practical Programming: An Introduction to Computer Science Using Python 3.6 (Paul Gries(著)、Jennifer Campbell(著)、Jason Montojo(著)、Pragmatic Bookshelf)のChapter 5(Making Choices)、Exercises 9、10、11の解答を求めてみる。

コード

Python 3

#!/usr/bin/env python3
from unittest import TestCase, main
from test.support import captured_stdout


class MyTestCase(TestCase):
    def setUp(self):
        pass

    def tearDown(self):
        pass

    def test9(self):
        ph = 2
        with captured_stdout() as stdout:
            for ph in [2, 3, 7]:
                if ph < 3.0:
                    print(f'{ph} is VERY acidic! Be careful.')
                elif ph < 7.0:
                    print(f'{ph} is acidic.')
        s = '''2 is VERY acidic! Be careful.
3 is acidic.
'''
        self.assertEqual(stdout.getvalue(), s)

    def test10a(self):
        ph = 6.4
        with captured_stdout() as stdout:
            if ph < 7.0:
                print("It's acidic!")
            elif ph < 4.0:
                print("It's a strong acid!")
        self.assertEqual(stdout.getvalue(), "It's acidic!\n")

    def test10b(self):
        ph = 3.6
        with captured_stdout() as stdout:
            if ph < 7.0:
                print("It's acidic!")
            elif ph < 4.0:
                print("It's a strong acid!")
        self.assertEqual(stdout.getvalue(), "It's acidic!\n")

    def test10c(self):
        ph = 3.6
        with captured_stdout() as stdout:
            if ph < 7.0:
                print("It's acidic!")
            if ph < 4.0:
                print("It's a strong acid!")
        s = '''It's acidic!
It's a strong acid!
'''
        self.assertEqual(stdout.getvalue(), s)

    def test11(self):
        with captured_stdout() as stdout:
            for age in [44, 45]:
                is_young = age < 45
                for bmi in [21, 22]:
                    is_heavy = bmi >= 22.0
                    if is_young:
                        if is_heavy:
                            risk = 'medium'
                        else:
                            risk = 'low'
                    else:
                        if is_heavy:
                            risk = 'high'
                        else:
                            risk = 'medium'
                    print(risk)
        output = '''low
medium
medium
high
'''
        self.assertEqual(stdout.getvalue(), output)


if __name__ == '__main__':
    main()

入出力結果(Bash、cmd.exe(コマンドプロンプト)、Terminal、Jupyter(IPython))

$ ./sample9.py -v
test10a (__main__.MyTestCase) ... ok
test10b (__main__.MyTestCase) ... ok
test10c (__main__.MyTestCase) ... ok
test11 (__main__.MyTestCase) ... ok
test9 (__main__.MyTestCase) ... ok

----------------------------------------------------------------------
Ran 5 tests in 0.001s

OK
$