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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 ]
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Python Interface Vs. Class: What's the Difference

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Here are the differences between Class and Interface in Python.

Python interface


Python class can have all concrete methods. But interface does not have single concrete method.


Here you'll know about

  • What's abstract method
  • Abstract Class: How to Create it
  • Rules to Write an Interface
  • How to Create Abstract Class
  • How to Create an Interface


What's abstract method

The abstrcat method is one which does not have body.

from abc import ABC, abstract method
class name_class(ABC): # abstract class

@abstractmethod
def name_method(self): #abstract method without body
pass


The interface is used when all the features are needed to be implemented differently for different objects.

Rules to Write an Interface

  1. All methods of an interface should be abstract.
  2. You cannot create an interface object.
  3. If any class implements an interface, then you need to define all the methods given in that interface in child class.
  4. You need to declare all methods as abstract if that class does not implement the interface

How to Create Abstract Class


from abc import ABC, abstractmethod
class Myengineer(ABC):
@abstractmethod
def mybranch(self):
pass
myobj = Myengineer()


Output

TypeError: Can’t instantiate abstract class Myengineer
with abstract methods mybranch


How to Create an Interface

You cannot create an object from an abstract class. But you can do it by creating a child class.


from abc import ABC, abstractmethod

#Abstract class

class Myengineer(ABC):
@abstractmethod
def mybranch(self):
pass

#Child class implements abstract class

class MyEEE(Myengineer):
def mybranch(self):
print(“I am an electrical and electronics Engineer”)
myobj = MyEEE()
myobj.mybranch()

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