Python int() Function

The Python int() function converts a given object to an integer or converts a decimal (floating-point) number to its integer part by truncating the fractional part.

Example: In this example, we passed a string as an argument to the int() function and printed it.

Output:

age = 21

Python int() Function Syntax

The syntax of the int() function in Python is as follows:

Syntax: int(x, base)

• x [optional]: string representation of integer value, defaults to 0, if no value provided.
• base [optional]: (integer value) base of the number.

Returns: Return decimal (base-10) representation of x

Python int() Function Examples

Let us see a few examples of int() in Python.

Python int() with different DataTypes

In this example, we passed a string, a float, and an integer value as a parameter to the int() function in Python to see how the input is affected by applying the int() function.

Output :

int('9')) = 9
int(9.9) = 9
int(9) = 9

Convert base using int() in Python

In this example, we used the int() function to convert the base of a number from Binary, Octal, and Hexadecimal to a Decimal integer.

Output : 

int() on 0o12 = 10
int() on 0b110 = 6
int() on 0x1A = 26

Exception of int() in Python

TypeError: raises TypeError when any object that does not have __int__() or __index__() Python magic methods implemented.

ValueError: raises ValueError when any object cannot be converted to an integer.

TypeError: int() can't convert non-string with explicit base

In this example, we are trying to convert a binary number to a decimal number using the Python int() function. But this code will raise an error as the binary number passed is not in a single quote.

Output:

TypeError: int() can't convert non-string with explicit base

ValueError: invalid literal for int() with base 10: 'geeks'

This example will generate a value error as we are passing a Python String to the int() function.

Output:

ValueError: invalid literal for int() with base 10: 'geeks'

Python int() Function for Custom Objects

The int() in Python can be used on custom objects. Let us see a few examples of the same.

int() with __int__() function

In this example, we created a class called Number and defined a __int__() method that returns the integer value. Then we created an object called data of the Number class. When we pass this object to the int() function, Python internally invokes the __int__() method, and the returned value is used as the integer representation.

Output:

number = 7

int() with __index__() function

In this example, we created a class called 'Number' and defined a value and a function that returns the value. Then we created an object called 'data' of the Number class which invokes the __index__() method. The data object stores the value that is returned by that method and then using the int() function we printed the value.

Output:

number = 7