# Python program to convert an integer number to octal

### How to convert an integer number to octal string in python :

Python comes with one built-in method *oct()* for converting an integer number to octal easily. You need to pass one integer number to this method. It will convert the integer to octal string and returns the value. One thing you should note that the returned octal string is prefixed with *0o*.If the parameter value is not a *python int*, it should define *__index__()* method that returns an integer.

The syntax of the *oct()* method is as below :

oct(x)

where, *x* is an integer number in *binary, decimal or hexadecimal* format. As explained above, the return value is an octal representation of the integer number *x*.

### Example :

Let’s try *oct()* with a *binary, decimal and hexadecimal* number.

print("octal representation of 10 is ", oct(10)) print("octal representation of 0xC is ", oct(0xC)) print("octal representation of 0b1010 is ", oct(0b1010))

It will print out the below output :

octal representation of 10 is 0o12 octal representation of 0xC is 0o14 octal representation of 0b1010 is 0o12

### Explanation :

1. The first number is decimal *10*. Octal representation of *10* is *12*. Note that the output is prefixed with *0o*.

2. The second number is the hexadecimal representation of *12*. Octal representation of *12* is *14*. So, the result is *0o14*.

3. The last number is a binary number, which is the binary representation of *10*. This is the reason the output of the first and the third line is the same.

We have tried *oct()* with *decimal, hexadecimal* and *binary* number in the above example. Now, let’s try it with a custom object.

### Find oct() for a custom object :

As mentioned before, for a custom object, we need to implement *__index__()* method, that will return an integer if we want to find the octal value for that object. Let’s do that :

class Student: rank = 73 def __index__(self): return self.rank def __int__(self): return self.rank student = Student() print("oct value of \'student\' is", oct(student))

Output :

oct value of 'student' is 0o111

The above program is also available on Github.

### Conclusion :

octal conversion is easy to implement in python using *oct()* method. Go through the examples above and try to run each one on your machine. If you have any queries, drop a comment below.