4. Functions

  • Gives possibility to reuse code,

  • Gives as chance to track code,

  • Splitting is more logical than executing code line by line

Different definitions of functions

def function_a():
    """"Docstring documenting function"""

    print('This is simple function')

# "Execution" of a function
function_a()

This is simple function

4.1. Function with parameteres

def sum_of_three_numbers(a, b, c):
    """Function calculating sum of three numbers"""

    print(a + b + c)

result = sum_of_three_numbers(3, 5, 8)
print(result)

16
None

def sum_of_four_numbers(a, b, c=0, d=0):
    """Simple function suming 4 numbers with default 4th param"""

    return (a + b + c + d)

print(sum_of_four_numbers(3, 5))
print(sum_of_four_numbers(3, 5, 8))
print(sum_of_four_numbers(3, 5, 8, 16))

8
16
32

4.2. Args

def sum_of_many(show, *nums):
    res_sum = 0

    for num in nums:
        res_sum += num

    if show:
        print('Sum equals to {}'.format(res_sum))
    return res_sum

res = sum_of_many(True, 1, 2, 3, 4, 5, 6, 7)
print(res)

Sum equals to 28
28

4.3. Kwargs

def res_salary_sum(**kwargs):
    """Sums all people"""

    res_sum = 0

    for person, salary in kwargs.items():
        res_sum += salary
    return res_sum

print(res_salary_sum(Adam=3000, Tomek=2500, Kasia=4320))

9820

4.4. Exercises part 1

  1. Create function checking if person is adult

  2. Function should use 2 arguments (name of person and age)

4.5. Exercises part 2

  • Create function which would be checking strength of password (own algorithm)

  • Password can have at least 6 characters

  • Password is stronger, when:

    • It has uppercase letters,

    • Has numbers,

    • Has special character (you can define list of special characters on your own ex. ['_', '*', '&'])

4.6. Exercises part 3

  1. Modify code calculation BMI - now it should be function

  • Takes additional parameter - name,

4.7. Exercises part 4

  • Create function report_salary(team, stats=True, *args) which for specific team returns average salary of the team, round the result to the 2nd decimal place

  • Additionaly if flag stats is on print statistics:

    • Average,

    • Median,

    • Minimal value,

    • Maximal value

Hint

To calculate median either you can create own function. But also you can create function form libraries.