martineharrison / MP3

MP3: Classes

Part 1: Rectangle

Define a class Rectangle which stores the bottom-left coordinates (x0, y0) and top-right coordinates (x1, y1) for each instance. The class should have the following methods:

def __init__(self, x0: float, y0: float, x1: float, y1: float):
    ...

def area(self) -> float:
    """Returns the area of the rectangle."""
    ...

def contains(self, x: float, y: float) -> bool:
    """Returns true iff the point (x, y) falls within the rectangle"""
    ...

What to turn in

• A class definition Rectangle defined as above
• A few basic assert tests of the area and contains methods
• A brief (paragraph or so) description of your approach and any challenges you ran into

Hints

• Look up the formula for the area of a rectangle, if you need to
• Remember that you can't write a < x < b in Python; instead, you have to write a < x and x < b

Stretch goal

Modify the class so that instead of storing the bottom-left and top-right coordinates, you simply store the bottom-left coordinates, the height, and the width, of the rectangle.

Part 2: Employee and file reader

Define a class Employee which stores an employee's name, title, and employee ID, as follows.

def __init__(self, name: str, title: str, employee_id: int):
    ...

Then, define a function or generator which reads Employee data from a text file and yields fully-populated Employee instances.

from typing import Iterator


def read_employees(path: str) -> Iterator[Employee]:
    ...

This function should assume the data is formatted similarly to the attached employees.txt.

What to turn in

• A class definition Employee defined as above
• A function or generator read_employees defined as above
• A few basic assert tests of read_employees
• A brief (paragraph or so) description of your approach and any challenges you ran into

Hints

• Use the with construction in read_employees
• An example of reading four lines at a time appears in Lecture 8