Python - int()

The int() function returns integer object from a float or a string containing digits.

>>>int(10)
10
>>>int(10.55)
10
>>>int(0.45)
0
>>>int('11')
11

To convert octal number to integer in decimal number system

>>>int('12',8)
10

Second parameter to the function is the base of number system. Here ‘12’ is string representation of octal number that is equivalent to 10 (Ten) in decimal number system (with base=10).

Similarly, Hexadecimal number (with base=16) is converted to decimal number.

>>>int('12',16)
18

Remember that string is converted to integer only if it is made of digits only. For string containing non-digit characters, int() function encounters following error:

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