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Step-by-Step Guide to Reading Different Files in Python

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 In the world of data science, automation, and general programming, working with files is unavoidable. Whether you’re dealing with CSV reports, JSON APIs, Excel sheets, or text logs, Python provides rich and easy-to-use libraries for reading different file formats. In this guide, we’ll explore how to read different files in Python , with code examples and best practices. 1. Reading Text Files ( .txt ) Text files are the simplest form of files. Python’s built-in open() function handles them effortlessly. Example: # Open and read a text file with open ( "sample.txt" , "r" ) as file: content = file.read() print (content) Explanation: "r" mode means read . with open() automatically closes the file when done. Best Practice: Always use with to handle files to avoid memory leaks. 2. Reading CSV Files ( .csv ) CSV files are widely used for storing tabular data. Python has a built-in csv module and a powerful pandas library. Using cs...
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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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