Python Method

 

Method in Python

• Method is nothing but a function defined inside a class.

Syntax : 

            keyword_class class_name :

                        keyword_def method_name() :

                                        statement 1

                                        statement 2

Example : 

 #program to define method

 class Employee_data :

     def assign_employee_data(self):
         self.name = "Techno Xpresss"

     def display_employee_data(self,):
         print("name :", self.name)

• With the help of Object (reference to class), method can be called

Syntax : 

            object_name = class_name()

            object_name . method_name()

Example : 

 #program

 class Employee_data :                        # class 

     def assign_employee_data(self):          # method
         self.name = "Techno Xpresss"

     def display_employee_data(self,):        # method
         print("name :", self.name)

 emp_1 = Employee_data()                      # object creation

 emp_1.assign_employee_data()                 # method calling with object
 emp_1.display_employee_data()

 #Output
name : Techno Xpresss

• It is a collection of statement(s) to perform operations.

 #program

 class Employee_data :

     def operations(self, a, b):
         print("sum : ", a + b)
         print("sub : ", a - b)
         print("mul : ", a * b)
         print("div : ", a / b)

     def assign_employee_data(self):
         self.name = "Techno Xpresss"

     def display_employee_data(self,):
         print("name :", self.name)
   

 #Output

 sum :  13
 sub :  7
 mul :  30
 div :  3.3333333333333335

• Once defined can be called many times.

 #program 

 class Employee_data :

     def operations(self, a, b):
         print("sum : ", a + b)

 emp_1 = Employee_data()
 emp_1.operations(10,5)
 emp_1.operations(1,50)
 emp_1.operations(15,25)
 emp_1.operations(16,35)

 #Output

 sum :  15
 sum :  51
 sum :  40
 sum :  51

• Method can be defined in 4 ways
• without parameter without return

 #program 

 class Employee_data :

     def operations(self):
         print("this is without parameter without return method")

 emp_1 = Employee_data()
 emp_1.operations()

 #Output

 this is without parameter without return method

• with parameter without return

 #program

 class Employee_data :

     def operations(self, a, b):
         sum = a+b
         print("this is with parameter without return method")

 emp_1 = Employee_data()
 emp_1.operations(10, 20)

 #Output

 this is with parameter without return method

• without parameter with return

 #program

 class Employee_data :

     def operations(self):
         sum = 10 + 20
         print("this is without parameter with return method")
         return sum

 emp_1 = Employee_data()
 result = emp_1.operations()
 print("return from method : ", result)

 #Output

 this is without parameter with return method
 return from method :  30

• with parameter with return

 #program

 class Employee_data :

     def operations(self, a, b):
         sum = a + b
         print("this is with parameter with return method")
         return sum

 emp_1 = Employee_data()
 result = emp_1.operations(10,15)
 print("return from method : ", result)

 #Output

 this is with parameter with return method
 return from method :  25

• Methods are of 3 types : 
• Static Method

 #program to define static method 

 class Employee_data :
     @staticmethod
     def operations():
         print("this is static method")

method defined under decorator @staticmethod

>>>>>

• Class method

 #program to define class method

 class Employee_data :
     @classmethod
     def operations(cls):
         print("this is class method")

method defined under decorator @classmethod

>>>>>

• Instance method

 #program to define instance class

 class Employee_data :
     def operations(self):
         print("this is instance method")

method defined without any decorator 

>>>>>