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Python map() and lambda() Use Cases and Examples

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 In Python, map() and lambda functions are often used together for functional programming. Here are some examples to illustrate how they work. Python map and lambda top use cases 1. Using map() with lambda The map() function applies a given function to all items in an iterable (like a list) and returns a map object (which can be converted to a list). Example: Doubling Numbers numbers = [ 1 , 2 , 3 , 4 , 5 ] doubled = list ( map ( lambda x: x * 2 , numbers)) print (doubled) # Output: [2, 4, 6, 8, 10] 2. Using map() to Convert Data Types Example: Converting Strings to Integers string_numbers = [ "1" , "2" , "3" , "4" , "5" ] integers = list ( map ( lambda x: int (x), string_numbers)) print (integers) # Output: [1, 2, 3, 4, 5] 3. Using map() with Multiple Iterables You can also use map() with more than one iterable. The lambda function can take multiple arguments. Example: Adding Two Lists Element-wise list1 = [ 1 , 2 , 3 ]

3 Exclusive Access Modifiers in Python

Here are three access modifiers in Python - Public, Protect, and Private. Access modifiers control the access to a variable/or method. 

You may have a question that does python supports access modifiers? The answer is yes.

In general, all the variables/or methods are public. Which means accessible to other classes. The private and protect access modifiers will have some rules. And the notation for protect and private are different. The single underscore is for protected and the double underscore is for private. Here is how to find Python list frequent items.

Differences between Public, Protect and Private


Here's Why You Need Access Modifiers in Python



Public access modifier

Public variables are accessible outside the class. So in the output, the variables are displayed.

class My_employee:

    def __init__(self, my_name, my_age):
        self.my_name = my_name  #public
        self.my_age = my_age   # public


my_emp = My_employee('Raj',34)
print(my_emp.my_name)
print(my_emp.my_age)

my_emp.my_name = 'Rohan'
print(my_emp.my_name)

Output

Raj
34
Rohan

** Process exited - Return Code: 0 **
Press Enter to exit terminal

Protect access modifier

Method of protection can be accessible within the class and subclass. From child class, you can access it. However, you cannot access it from outside the class. 

class parent:
    def __init__(self):
        pass
    def _test1(self):  # protected
        print("I am in Parent")

class child(parent):
    def __init(self):
        pass
    def test2(self):  
        print("I am in child class")

obj1=child()
obj1._test1()


Output

I am in Parent

** Process exited - Return Code: 0 **
Press Enter to exit terminal

Private access modifier

Below, you will find an error in the output. It is because the method in the parent is private, and the child class tried to access it. The bottom line is only the parent class can access it - not possible even by the subclass, also outside the class.  

class parent:
    def __init__(self):
        pass
    def __test1(self):  #provate
        print("I am in Parent")

class child(parent):
    def __init(self):
        pass
    def test2(self):   
        print("I am in child class")

obj1=child()
obj1.__test1()

Output

Traceback (most recent call last):
  File "main.py", line 14, in <module>
    obj1.__test1()
AttributeError: 'child' object has no attribute '__test1'


** Process exited - Return Code: 1 **
Press Enter to exit terminal

We are restricting the access to methods and variables resulting in prevention of data from direct modification. So, the process of data binding is called encapsulation. It is one of the fundamental concepts in object-oriented programming (OOP).

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