Python oct() Method
The python oct() is a built-in function of python that returns the octal string of a given integer. Octal strings start with 0o prefix when converted.
The Python oct() built-in function converts an integer to its octal (base-8) string representation. It accepts a single parameter, an integer value, which can be specified in decimal, binary, or hexadecimal notation. The function returns a string prefixed with 0o that represents the octal equivalent of the given integer. If the argument is not an int, the object must implement the __index__() method to return an integer. Octal representation is commonly used in Unix and Linux file permission systems, where permission modes like 0o755 or 0o644 define read, write, and execute access for owner, group, and others. It is also used in low-level programming, embedded systems, and legacy codebases that rely on base-8 encoding for compact representation of binary data groups of three bits each.
What does oct() return?
The oct() function returns a string representing the octal value of the given integer, prefixed with 0o to indicate base-8 notation.
When should you use oct()?
Use oct() when you need to convert an integer to its octal string representation, such as when working with Unix file permissions, low-level bit manipulation, or displaying numbers in base-8 format for debugging or educational purposes.
The syntax of oct() is:
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oct(integer)
oct() Parameters
The oct() function takes only one parameter argument.
- integer - an integer number that can be binary, decimal or hexadecimal.
Let check the example of oct() in python.
Example 1: How to use oct() function in python?
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# decimal to octal
print('oct(10) is:', oct(4))
# binary to octal
print('oct(0b101) is:', oct(0b10))
# hexadecimal to octal
print('oct(0XA) is:', oct(0XC))
Output:
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oct(10) is: 0o4
oct(0b101) is: 0o2
oct(0XA) is: 0o14
Example 2: How to use the oct() function with a custom object?
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class Person:
age = 23
def __index__(self):
return self.age
def __int__(self):
return self.age
person = Person()
print('The oct is:', oct(person))
Output:
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The oct is: 0o27
Here, the Person class implements __index__() and __int__(). That’s why we can use oct() on the objects of Person.
Common Use Cases
Working with Unix file permissions is the most common real-world application of oct(). When you retrieve file permission modes using os.stat(), the result is an integer that you can pass to oct() to display the familiar octal permission format like 0o755, making it easy to understand and communicate access rights.
Converting between number bases for educational or debugging purposes is another frequent use case. Developers often use oct() alongside bin() and hex() to visualize how the same integer looks in different bases, which is helpful when learning about number systems or troubleshooting bitwise operations.
Encoding data in legacy systems that use octal notation is a more specialized application. Some older protocols, serial communication formats, and mainframe systems use octal encoding, and oct() provides a straightforward way to produce the required format from standard Python integers.
For related base conversion functions, see the Python hex() function for hexadecimal conversion and the Python bin() function for binary conversion.
Rules of oct()
- If not an integer, it should implement __index__() to return an integer.
- The oct() function will raise an error when a non-integer value is passed.
Machine Learning Engineer at Codiste, specializing in Generative AI, NLP, and Computer Vision. Building production AI systems with Python.