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Python Set Operations Explained: From Theory to Real-Time Applications

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A  set  in Python is an unordered collection of unique elements. It is useful when storing distinct values and performing operations like union, intersection, or difference. Real-Time Example: Removing Duplicate Customer Emails in a Marketing Campaign Imagine you are working on an email marketing campaign for your company. You have a list of customer emails, but some are duplicated. Using a set , you can remove duplicates efficiently before sending emails. Code Example: # List of customer emails (some duplicates) customer_emails = [ "alice@example.com" , "bob@example.com" , "charlie@example.com" , "alice@example.com" , "david@example.com" , "bob@example.com" ] # Convert list to a set to remove duplicates unique_emails = set (customer_emails) # Convert back to a list (if needed) unique_email_list = list (unique_emails) # Print the unique emails print ( "Unique customer emails:" , unique_email_list) Ou...
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How to Work with 'Pointers' in Python

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Pointers denote an address (memory location). It has three identities - Name, Value, and Location (Address). Python doesn't support pointers as-is. You need to import 'ctypes' package to work with C Language.

Note: Pointer is popular in C, C++. The called module just uses the value of Pointer (not address).  Below is my detailed post on pointers.  


An article on how to work with pointers


How to work with Pointers

  • To pass a reference(address) to the C interface.
  • You can use C Language in Python by importing 'ctypes.' 

Pointer Notation

1. Value
2. Address
3. Name

Python Pointers


Python doesn't support pointers. C and C++ extensively support pointers. Pointer is nothing but an ADDRESS. It is immutable. That means you can't change the value. Python supports pointers for the purpose to interact with C Language.



Pointers

How to Import 'ctypes'

  1. Import 'ctypes' library for the purpose of working with C language. 
  2. Here's how to import 'ctypes' for windows and Linux.

How to denote Pointers

Here's the way to denote pointers in Python. Check out here Python Pointers.

  
from ctypes import * 
i = c_int(42) 
pi = pointer(i)


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