Polygon Area Calculator (Python)

This project is part of the freeCodeCamp Python Certification.

It implements a simple geometry calculator using object-oriented programming. The application models rectangles and squares, allowing users to compute geometric properties and visualize shapes using text-based output.

---

📌 Features

• Create rectangles with custom width and height
• Create squares as a special case of rectangles
• Calculate area of shapes
• Calculate perimeter of shapes
• Compute the diagonal using $d = \sqrt{width^2 + height^2}$
• Generate a text-based visual representation of the shape
• Modify dimensions dynamically (width, height, or side)
• Determine how many times one shape fits inside another

---

🛠️ Technologies

• Python 3

---

📖 User Stories

1. You should create a Rectangle class.

2. When a Rectangle object is created, it should be initialized with width and height attributes. The class should also contain the following methods:

   • set_width: Sets the width of the rectangle.
   • set_height: Sets the height of the rectangle.
   • get_area: Returns area $(width×height)$ .
   • get_perimeter: Returns perimeter $2(width+height)$ .
   • get_diagonal: Returns diagonal $\sqrt{width^2 + height^2}$ .
   • get_picture: Returns a string that represents the shape using lines of *. The number of lines should be equal to the height and the number of * in each line should be equal to the width. There should be a new line (\n) at the end of each line. If the width or height is larger than 50, this should return the string: Too big for picture..
   • get_amount_inside: Takes another shape (square or rectangle) as an argument. Returns the number of times the passed in shape could fit inside the shape (with no rotations). For instance, a rectangle with a width of 4 and a height of 8 could fit in two squares with sides of 4.

3. If an instance of a Rectangle is represented as a string, it should look like: Rectangle(width=5, height=10).

4. You should create a Square class that subclasses Rectangle.

5. When a Square object is created, it should be initialized with a single side length. The __init__ method should store the side length in both the width and height attributes from the Rectangle class.

6. The Square class should contain the following methods:

   • set_width: Overrides the set_width method from the Rectangle class. It should set the width and height to the side length.
   • set_height: Overrides the set_height method from the Rectangle class. It should set the width and height to the side length.
   • set_side: Sets the height and width of the square equal to the side length.

7. The Square class should be able to access the Rectangle class methods.

8. If an instance of a Square is represented as a string, it should look like: Square(side=9).

Here is an example usage:

rect = Rectangle(10, 5)
print(rect.get_area())
rect.set_height(3)
print(rect.get_perimeter())
print(rect)
print(rect.get_picture())

sq = Square(9)
print(sq.get_area())
sq.set_side(4)
print(sq.get_diagonal())
print(sq)
print(sq.get_picture())

rect.set_height(8)
rect.set_width(16)
print(rect.get_amount_inside(sq))

And here is an example of the output:

50
26
Rectangle(width=10, height=3)
**********
**********
**********

81
5.656854249492381
Square(side=4)
****
****
****
****

8

---

🧪 Example Usage

Example test cases are included as commented lines at the bottom of main.py.

Uncomment them to run and see the output.

---

📚 Notes

• This project was developed to meet the certification requirements.
• The implementation focuses on correctness and clarity rather than extended functionality.