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Python Object-Oriented Python Dice Roller Boards

Suwijuk Nawaphanarat
Suwijuk Nawaphanarat
2,103 Points
Posted by Suwijuk Nawaphanarat
Suwijuk Nawaphanarat
2,103 Points

I need help for someone to explain what is Subclass

I keep forgetting what is Subclass every single time when the question asked me to create a new Subclass. Where is this Subclass in a Class function? I appreciate your help. Thanks!

boards.py 
class Board:
    def __init__(self, width, height):
        self.width = width
        self.height = height
        self.cells = []
        for y in range(self.height):
            for x in range(self.width):
                self.cells.append((x, y))

2 Answers

Mark Filter
Mark Filter
32,718 Points
Mark Filter
Mark Filter
32,718 Points

In a more theoretical explanation, a SUB-CLASS, aka CHILD-CLASS, aka DERIVED-CLASS is a class that is a copy of a previously defined class, but with the intention of customizing it for a more specific purpose. The changes could be subtle or substantial. For instance, you could be building a banking application. You would probably have at least two different types of banking accounts in this application: (1) Checking and (2) Savings. Both account types have similar qualities, but have some differences as well. You could create a SUPER-CLASS, aka PARENT-CLASS, that would ENCAPSULATE (or contain) the similarities and then create SUB-CLASSES to handle the peculiarities of each specific account type. It would look something like this:

  • Account: ABSTRACT PARENT CLASS - has account number, balance, methods for withdrawal & deposit, etc.
    • CHECKING ACCOUNT - (has all the above, plus...), does not earn interest
    • SAVINGS ACCOUNT - (has the same as Account Class, plus...) does earn interest
Jon Mirow
Jon Mirow
9,864 Points
Jon Mirow
Jon Mirow
9,864 Points

Hi there!

I believe we're talking about an inherited class, or child class. So a subclass wouldn't be inside the Board class you have there, but a class that inherits from it:

class Plank(Board):
    """
    A narrow type of board
    """

    def __init__(self):
        super().__init__(2, 4)

Hope it helps :)