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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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3 Best Methods to Read Files in Python

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Read file line by line

Python supports three specific methods to read files- read, readline, readlines. All these you use on files. Each has its unique purpose. Below are the best examples.

3 Methods to read file

  1. read
  2. readline
  3. readlines

Method-1: read

It reads records from file in sequence.

Here, file.txt is sample file with single row.

file.txt


abcdefghijk

file_object.read(2) ==> you will get 'ab'

file_object.read(4)  ===> you will get 'cdef'


Here, the multiple read methods read the data in sequence. The read(x) method will read only the number of characters that mentioned in the read method. Again, if you give multiple read methods then it will read in sequence.


Method-2: readline


It reads the file line by line.

Here, file.txt is a file with single row.

file.txt

abcdefghijk

file_object.readline() ==> you will get 'abcdefghijk'

Here, it reads the file line by line.


Method-3: readlines

It reads all the records at a time.

Here, file.txt is a file with two rows.

file.txt

abcdefghijk
iiiooooooia

file_object.readlines() ==> you will get both the lines.


abcdefghijk
iiiooooooia

Here, it reads all the lines at a time.

Summary

  • I've demonstrated three methods
  • Useful for interviews and projects

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