Object Oriented Programming Basics

Object Oriented Programming

Classes and Objects

• A class is a blueprint for creating objects
• An object is an instance of a class
• Classes define properties (data) and methods (functions)

Class Syntax

• class ClassName: defines a class
• self parameter is a reference to the current instance of the class

Inheritance

• A child class can inherit properties and methods from a parent class
• class ChildClass(ParentClass): defines a child class that inherits from a parent class

Encapsulation

• Hiding internal implementation details from the outside world
• Using private variables (e.g. __private_variable) to restrict access

Polymorphism

• Ability of an object to take on multiple forms
• Method overriding: child class provides a different implementation of a method
• Method overloading: multiple methods with the same name but different parameters

Loops

For Loop

• for variable in iterable: iterates over an iterable (e.g. list, tuple, string)
• break statement exits the loop
• continue statement skips to the next iteration

While Loop

• while condition: loops while the condition is true
• break statement exits the loop
• continue statement skips to the next iteration

Loop Control Statements

• pass statement does nothing, used as a placeholder
• else clause executes when the loop finishes normally (not due to a break statement)

Iterating Over Dictionaries

• for key in dictionary: iterates over the keys
• for value in dictionary.values(): iterates over the values
• for key, value in dictionary.items(): iterates over the key-value pairs

Object Oriented Programming

Classes and Objects

• A blueprint for creating objects is defined by a class, which is a template
• An instance of a class is called an object, which has its own set of attributes and methods
• A class defines properties (data) and methods (functions) that can be used by objects

Class Syntax

• A class is defined using the class keyword followed by the class name and a colon
• The self parameter is a reference to the current instance of the class and is used to access class variables

Inheritance

• A child class can inherit properties and methods from a parent class using inheritance
• The parent class is specified in the child class definition using the syntax class ChildClass(ParentClass):
• Inheritance allows for code reuse and facilitates the creation of a hierarchy of classes

Encapsulation

• Encapsulation is the concept of hiding internal implementation details from the outside world
• Private variables can be used to restrict access to certain attributes or methods
• Private variables are denoted using a double underscore prefix (e.g.__private_variable)

Polymorphism

• Polymorphism is the ability of an object to take on multiple forms
• Method overriding is a type of polymorphism where a child class provides a different implementation of a method
• Method overloading is a type of polymorphism where multiple methods with the same name but different parameters can be defined

Loops

For Loop

• A for loop is used to iterate over an iterable (e.g. list, tuple, string)
• The syntax for a for loop is for variable in iterable:
• The loop will iterate over each item in the iterable and execute the code block
• The break statement can be used to exit the loop prematurely
• The continue statement can be used to skip to the next iteration

While Loop

• A while loop is used to execute a code block as long as a certain condition is true
• The syntax for a while loop is while condition:
• The loop will continue to execute as long as the condition is true
• The break statement can be used to exit the loop prematurely
• The continue statement can be used to skip to the next iteration

Loop Control Statements

• The pass statement is a placeholder that does nothing and can be used to avoid a syntax error
• The else clause is used to execute a code block when the loop finishes normally (not due to a break statement)

Iterating Over Dictionaries

• A for loop can be used to iterate over the keys of a dictionary using for key in dictionary:
• A for loop can be used to iterate over the values of a dictionary using for value in dictionary.values():
• A for loop can be used to iterate over the key-value pairs of a dictionary using for key, value in dictionary.items():