Skip to main content

Instance variables vs Class variables in Python

 


Learning Sections          show

Instance variables vs Class variables in Python

In Python, instance variables are variables that are bound to instances of a class, while class variables are variables that are bound to the class itself. Each instance of the class has its own copy of instance variables, while class variables are shared among all instances of the class.

Instance variables are defined within methods of a class using the self keyword, while class variables are defined directly within the class body.

Example:


class Car:
    # Class variable
    wheels = 4

    # Instance method to initialize instance variables
    def __init__(self, color):
        # Instance variable
        self.color = color

# Create instances of the Car class
car1 = Car('red')
car2 = Car('blue')

# Access instance variables
print(car1.color)  # Output: 'red'
print(car2.color)  # Output: 'blue'

# Access class variable
print(Car.wheels)  # Output: 4
    

Instance variables are specific to each instance of a class and are used to store unique data for each instance. Class variables, on the other hand, are shared among all instances of the class and are typically used to store data that is common to all instances.

Differences:

  • Instance variables are specific to each instance of a class, while class variables are shared among all instances of the class.
  • Instance variables are defined within methods of a class using the self keyword, while class variables are defined directly within the class body.
  • Each instance of a class has its own copy of instance variables, while class variables are shared by all instances of the class.
  • Instance variables are used to store unique data for each instance, while class variables are typically used to store data that is common to all instances.

Popular posts from this blog

Generators in Python

  Learning Sections          show Generators in Python Generators are a special type of iterator in Python that allow you to iterate over a sequence of items without storing them all in memory at once. They are useful for generating large sequences of data on-the-fly, or for processing data in a memory-efficient manner. Creating Generators In Python, generators are created using generator functions or generator expressions: # Generator function def my_generator ( n ): for i in range ( n ): yield i # Generator expression my_generator = ( i for i in range ( 10 )) A generator function uses the yield keyword to yield values one at a time, while a generator expression creates an anonymous generator. Iterating Over Generators You can iterate over the values produced by a generator using a for loop: for value in my_generator ( 5 ): print ( value ) This w...

Inheritance in Python

  Learning Sections          show Inheritance in Python Inheritance is a fundamental concept in object-oriented programming (OOP) that allows a class to inherit attributes and methods from another class. The class that inherits is called the child class or subclass, and the class being inherited from is called the parent class or superclass. Basic Inheritance In Python, a child class inherits from a parent class by specifying the parent class in parentheses after the child class name. Example: class Animal : def __init__ ( self , name ): self . name = name def speak ( self ): raise NotImplementedError ( "Subclass must implement this method" ) class Dog ( Animal ): def speak ( self ): return "Woof!" class Cat ( Animal ): def speak ( self ): return "Meow!" # Create instances of Dog and Cat dog = Dog ( "Buddy" ) cat = Cat ( "Whiskers" ...

If else Conditional Statements in Python

  Learning Sections     show If-Else Conditional Statements Conditional statements allow you to execute different blocks of code based on certain conditions. The most common conditional statement is the if statement. It can be used alone, or combined with elif (else if) and else statements to handle multiple conditions. If Statement The if statement evaluates a condition, and if the condition is true, the block of code indented under the if statement is executed. # If statement example x = 10 if x >> 0 : print ( "x is positive" ) If-Else Statement The if-else statement adds an additional block of code that runs if the condition is false. # If-else statement example x = -10 if x >> 0 : print ( "x is positive" ) else : print ( "x is non-positive" ) If-Elif-Else Statement The if-elif-else statement allows you to check multiple conditions. The fir...