Python - Storing Data Using Other Collection Types - Set(要素数(len関数)、popメソッド)、Tuple、Dictionary(itmesメソッド)

Practical Programming
楽天ブックス 紀伊国屋書店

開発環境

• macOS Catalina - 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 11(Storing Data Using Other Collection Types)、Exercise 3、4、5、6の解答を求めてみる。

コード

#!/usr/bin/env python3
from unittest import TestCase, main
from typing import Any, List, Set, Tuple, Dict, TextIO
from io import StringIO

print('3, 4, 5, 6.')


class TestMatingPairs(TestCase):
    def test_empty(self):
        self.assertEqual(mating_pairs(set(), set()), set())

    def test_one(self):
        self.assertEqual(mating_pairs({1}, {2}), {(1, 2)})

    def test_other(self):
        males = {0, 2}
        females = {1, 3}
        pairs = mating_pairs(males, females)
        self.assertTrue(pairs == {(0, 1), (2, 3)} or
                        pairs == {(0, 3), (2, 1)})


class TestAuthorsFromFile(TestCase):
    def test_empty(self):
        instring = '''COMPND TEST
ATOM 1 N 0.1 0.2 0.3
ATOM 2 N 0.2 0.1 0.0
END
'''
        infile = StringIO(instring)
        self.assertEqual(get_authors_from_file(infile), set())

    def test_one(self):
        instring = '''AUTHOR author name
COMPND TEST
ATOM 1 N 0.1 0.2 0.3
ATOM 2 N 0.2 0.1 0.0
END
'''
        infile = StringIO(instring)
        self.assertEqual(get_authors_from_file(infile), {'author name'})

    def test_other(self):
        instring = '''AUTHOR author name
COMPND TEST
ATOM 1 N 0.1 0.2 0.3
ATOM 2 N 0.2 0.1 0.0
AuTHor author name1

author author name

END
'''
        infile = StringIO(instring)
        self.assertEqual(get_authors_from_file(infile),
                         {'author name', 'author name1'})


class TestDistinctValues(TestCase):
    def test(self):
        self.assertEqual(coun_values({'red': 1, 'green': 1, 'blue': 2}), 2)


class TestLeastLikelyObserved(TestCase):
    def test(self):
        self.assertEqual(least_likely_observed(
            {'neutron': 0.55, 'proton': 0.21, 'meson': 0.03, 'meson': 0.03,
             'muon': 0.07, 'neutrino': 0.14}),
            'meson')


def mating_pairs(males: set, females: set) -> Set[Tuple[Any, Any]]:
    pairs = set()
    for _ in range(len(males)):
        pairs.add((males.pop(), females.pop()))
    return pairs


def get_authors_from_file(reader: TextIO) -> Set[str]:
    return {line[6:].strip()
            for line in reader if line.lower().startswith('author')}


def get_authors(filename: str) -> Set[str]:
    with open(filename) as f:
        authors = get_authors_from_file(f)
    return authors


def coun_values(d: dict) -> int:
    return len(set(d.values()))


def least_likely_observed(d: Dict[str, int]) -> str:
    s = ''
    m = 1
    for k, v in d.items():
        if v < m:
            s = k
            m = v
    return s


if __name__ == "__main__":
    main()

入出力結果(Zsh、PowerShell、Terminal、Jupyter(IPython))

% ./sample3.py -v
3, 4, 5, 6.
test_empty (__main__.TestAuthorsFromFile) ... ok
test_one (__main__.TestAuthorsFromFile) ... ok
test_other (__main__.TestAuthorsFromFile) ... ok
test (__main__.TestDistinctValues) ... ok
test (__main__.TestLeastLikelyObserved) ... ok
test_empty (__main__.TestMatingPairs) ... ok
test_one (__main__.TestMatingPairs) ... ok
test_other (__main__.TestMatingPairs) ... ok

----------------------------------------------------------------------
Ran 8 tests in 0.001s

OK
%