File Reading Using Python

Introduction to Python file reading using Python

In Python file reading using python, The file is a storing container that can be store related information. Paper document for a computer. Various types of files store different types of information such as for python coding file xyz.py file, for a text file, for graphic file, data file, directory file. They can be store permanently store data(i.e. Hard Disk).

Python File:

A basic operation in python by the following order while Python file reading using Python:

1. Open a file
2. Read a file
3. Write a file
4. Close the file

Text file:

Welcome to Fireblaze AI School.

Offer the best course for beginners.

Thank You.

Now, you can save this text file as sample.txt.

 Open a file

In python already built-in open() function to open a file.

For example:

f = open("machine learning/python/sample.txt")  # specifying full path


x = open("sample.txt")    # open file in current directory

Some specific modes in while opening a file. Such as to read r, for write w, and append a to the file. 

The default is reading in text mode.

Here, some example 

  x = open("sample.txt")      # read mode 'r' (default mode)
  x = open("sample.txt",'w')  # write in text mode
  x = open("img.sample",'r+b') # read and write in binary mode

Read a file

To read a file in python, we must use ‘r’ mode.

There are number of methods available for the reading purpose. but we can use ‘r’ (read) method to read in the size number of data.

Example:

x = open("sample.txt",'r',encoding = 'utf-8')
 x.read(4)    # read the first 4 data
 'fireblaze'

 x.read(4)    # read the next 4 data
 ' AI '
 x.tell()    # get the current file position
 14
 print(x.read())  # read the entire file
 Fireblaze AI School
 This file belong to data science project



 You can also read the file using for...loop.
 for line in x:
...    print(line, end = “ ”)
...
Fireblaze AI School
This file belongs to a data science project

Write a file

For a write a file in python, we need to open it in write ‘w’.

For binary file is used the write() method.

  with open("sample.txt",'w',encoding = 'utf-8') as f:
  f.write("sample file\n")
  f.write("In that file\n\n")

This program will create a new file named sample.txt in the current directory if it does not exist. If it does exist, it is overwritten.

Close the file

When, your programming task complete you need to properly close the file. Closing a file is done using the close() method available in python.

  x = open("sample.txt")
  # perform file operations 
  f.close()

Above close() function not safe.Some operation with the file, the program exits without closing file. Try below code:

try:

   x = open("sample.txt", encoding = 'utf-8')
   # perform file operations

finally:

   x.close()

Now file are properly closeed.