Open a File for Reading Without Specifying the Mode Python

Files are used to store and organize data on a disk. We oftentimes use files when nosotros need to store data permanently on a hd. For example, say we are edifice a software system that maintains student records. Now, we demand to store the student data permanently for future use. For this purpose, we tin apply files to store data, and subsequently on, we can open these files and access the stored data at any time.

Reading and writing files are very common functions in Python. Information technology is piece of cake to create, read, and edit files in Python. Python comes with congenital-in functions for reading and writing files. You can open, write, and read files using the Python born functions. The file operations are performed in the following sequence:

• Open a file
• Read/write file
• Close file

Using Python, you tin can create text files and binary files. Text files store data in the form of characters and each line ends in a newline grapheme ('\n'). In binary files, information is stored in the class of bytes (1 and 0).

In this article, you will larn:

• Some of the dissimilar file modes in Python
• How to open a file
• How to create a file
• How to write information to a file
• How to read a file

Dissimilar File Modes in Python

Modes in Python describe the type of functioning to be performed on the file. When opening a file, you must specify the mode. Every file has a file handle. The file handle acts like a cursor that specifies where to write and read information. It is a blazon of location pointer. The post-obit include some of the dissimilar access file modes in Python:

Fashion	Description
r	Opens the file in reading mode. This mode is selected past default if you do non ascertain any style while opening the file in Python.
w	Writes a file. This mode creates a file if the file does not exist already and overwrites the information in the file.
r+	Used to read and write the file. It shows an error if the file does not exist.
a	Opens the file in append mode. The file handle is located at the end of the file. This style does non overwrite the existing data just starts writing data at the cease of the file. A new file is created if the file does not exist.
a+	Opens the file for reading and writing. This opens the file in append mode for writing. The data is inserted at the end of the file. A new file is created if the file does not exist.
t	Opens the file in text mode.

How to Open a File

To open a file in Python, utilise the built-in open up() function. The open() function takes two arguments as an input, i.e., the proper noun of the file and the manner of operation. This function returns the file object equally an output. There is no need to import any module to use the open() role. The following is the syntax of the open() function:

file_object = open ("file_name", "mode")

Here, 'file_name' represents the proper noun of the actual text file, while 'fashion' represents the file access or file operation mode. Yous can besides identify r before 'file_name,' if the file proper noun includes special characters. The r is placed as follows:

=file_object = open (r"file_name", "mode")

For example, the file name could exist: "F:\newfolder\myfile.txt"

How to Create a File

The open() function can be used to create files in Python. Use the append mode (a) within the open() function to create the file. Create a file using the code given beneath:

file = open ( "sample.txt" , "a" )

Hither, a new file object is created. The file object is named "file." The name of the newly created text file is "sample.txt." The text file is opened in append mode. It will create the new file if the file does non exist already. After creating the file, you lot must close the file in the following fashion:

The built-in close() function is used to close the file.

How to Write Data to a File

There are ii functions in Python used for writing data in a file:

1. write()
2. writelines()

The write() function is used to write single line or single string information to a file, while the writelines() part is used to write multiple lines of data to a text file. Allow us see some examples of writing data to a file.

Using the write() Function

In this case, we are using the write() role to write data to a file. The file is opened in writing mode. "\n" is placed to specify the finish of the line.

# creating a new file object and opening a file in writing mode
file = open ( "sample.txt" , "w" )
#  writing unmarried line to a file

file.write ( "Welcome to the linuxhint \due north" )
#  writing another unmarried line to a file
file.write ( "Welcome back" )

#closing the file
file.shut ( )

Output

The lines have been written in the text files.

If we open up the file in writing mode and enquire the write() function to write more lines to the file, it will overwrite the previous data and new data will be added into the text file.

# creating a new file object and opening a file in writing fashion
file = open ( "sample.txt" , "w" )
#  writing unmarried line to a file

file.write ( "Hello Anybody \n" )
#  writing another single line to a file
file.write ( "This is the  replaced  string" )

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