Chapter “Programming languages”, exercise 3

Text

Following the template in Listing 11, write in Python the algorithm proposed originally in Figure 4 of the chapter “Algorithms” as a flowchart (which uses a different approach compared to the one discussed in the chapter about programming languages), and accompany such code with the related test function and some executions with varying values of input.

Answer

# Test case for the algorithm
def test_contains_word(first_word, second_word, bib_entry, expected):
    result = contains_word(first_word, second_word, bib_entry)
    if expected == result:
        return True
    else:
        return False


# Code of the algorithm
def contains_word(first_word, second_word, bib_entry):  # input/output: input two words and a bibliographic entry
    result = 0  # process: initialize the result value to 0

    if first_word in bib_entry:  # decision: the first word is in the bibliographic entry
        result = result + 1  # process: sum 1 to the result value

    if second_word in bib_entry:  # decision: the second word is in the bibliographic entry
        result = result + 1  # process: sum 1 to the result value

    return result  # input/output: return the result value


# Three different test runs
print(test_contains_word("Shotton", "Open",
                         "Shotton, D. (2013). Open Citations. Nature, 502: 295–297. doi:10.1038/502295a", 2))
print(test_contains_word("Citations", "Science",
                         "Shotton, D. (2013). Open Citations. Nature, 502: 295–297. doi:10.1038/502295a", 1))
print(test_contains_word("References", "1983",
                         "Shotton, D. (2013). Open Citations. Nature, 502: 295–297. doi:10.1038/502295a", 0))

Additional material

The runnable Python file is available online.