1 Overview

There are generally three styles of code found in Python.

• Procedural
• Object Oriented
• Functional

A single codebase may use one paradigm or a combination of paradigms.

def main():
    point1 = (0, 5)
    point2 = (8, 3)
    point3 = (1, 7)

    points = [point1, point2, point3]

    for point in points:
        print(sqrt(point[0] ** 2 + point[1] ** 2))

if __name__ == "__main__":
    main()

def main():
    points = [(0, 5), (8, 3), (1, 7)]

    for point in points:
        print(sqrt(point[0] ** 2 + point[1] ** 2))

if __name__ == "__main__":
    main()

class Point:
    def __init__(self, x, y):
        self.x = x
        self.y = y

    def magnitude(self)
        return sqrt(self.x ** 2 + self.y ** 2)

The main function would be near identical…

def main():
    points = [Point(0, 5), Point(8, 3), Point(1, 7)]

    for point in points:
        print(point.magnitude())

if __name__ == "__main__":
    main()

A proper discussion of object oriented Python would require explanation of the rules of a class checklist… But, those are topics for future discussion.

2.3 Functional

The functional approach would look at everything a list (more aptly, something that behaves like a list).

def main():
    points = [(0, 5), (8, 3), (1, 7)]

    distances = [sqrt(point[0] ** 2 +  point[1] ** 2) for point in points]

    shortest_distance = min(distances)
    largest_distance  = max(distances)
    average_distance  = sum(distances) / len(points)

Note how the distances are stored in a second list.

3 Concessions

Each piece of code could be improved. However, these improvements would require familiarity with topics such as generator expressions and dunder functions (which are covered in later modules).