In Python an strings can be converted into an integer using the Python built-in function. However, it’s important to note that the string must represent a valid integer value for the conversion to succeed.
Example
Input: str_num = "1001" Output: 1001 Explanation: In this, we are converting string into integer
Python Convert String to Int
In Python, you can convert a string into an integer using different functions in Python. This function takes a string as its argument and returns the corresponding integer value.
- Using int() function
- Using eval() function
- Using ast.literal_eval
- Using str.isdigit() function
Convert a string to a number Method
String to Int converter using int() function in Python
Here we will use int() function which will return the int data type.
Python3
num = '10' # check and print type num variable print ( type (num)) # convert the num from string into int converted_num = int (num) # print type of converted_num print ( type (converted_num)) # We can check by doing some mathematical operations print (converted_num + 20 ) |
<class 'str'> <class 'int'> 30
As a side note, to convert to float, we can use float() in Python
String to Int Converter Using Eval() Function
Here we will use eval() methods to Convert String to Int
Python3
# converting python string to # int using eval() function a = "100" print ( eval (a) + 12 ) |
112
String to Int Converter Using Ast.literal_eval
This function evaluates an expression node or a string consisting of a Python literal or container display.
Python3
from ast import literal_eval int_value = literal_eval( "1234" ) print (int_value) print ( type (int_value)) |
1234 <class 'int'>
String to Int Converter using str.isdigit()
Python isdigit() function returns a Boolean value TRUE if all the values in the input string are digits; else it returns FALSE.
Python3
string = "42" if string.isdigit(): integer = int (string) print (integer) # Output: 42 else : print (f "{string} is not a valid integer." ) |
42
Note: float values are decimal values that can be used with integers for computation.