{"id":162,"date":"2020-10-04T00:28:29","date_gmt":"2020-10-04T00:28:29","guid":{"rendered":"https:\/\/www.pythontutorial.net\/?page_id=162"},"modified":"2025-03-26T06:47:21","modified_gmt":"2025-03-26T06:47:21","slug":"python-type-conversion","status":"publish","type":"page","link":"https:\/\/www.pythontutorial.net\/python-basics\/python-type-conversion\/","title":{"rendered":"Python Type Conversion"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you’ll learn about type conversion in Python and some useful type conversion functions.<\/p>\n\n\n\n

Introduction to type conversion in Python #<\/a><\/h2>\n\n\n\n

To get input from users, you use the input()<\/code> function. For example:<\/p>\n\n\n

value = input('Enter a value:'<\/span>)\nprint(value)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
When you execute this code, it’ll prompt you for input on the Terminal:<\/p>\n\n\n
Enter a value:<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Enter a value:100<\/span>\n100<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Note that the Playground will display an input dialog instead of a prompt.<\/p>\n\n\n\n
The following example prompts you to enter two input values: net price and tax rate. After that, it calculates the tax and displays the result on the screen:<\/p>\n\n\n
price = input('Enter the price ($):'<\/span>)\ntax = input('Enter the tax rate (%):'<\/span>)\n\ntax_amount = price * tax \/ 100<\/span>\n\nprint(f'The tax amount price is ${tax_amount}<\/span>'<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
When you execute the program and enter some numbers:<\/p>\n\n\n
Enter the price ($):100<\/span>\nEnter the tax rate (%):10<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
… you’ll get the following error:<\/p>\n\n\n
Traceback (most recent call last):\n  File \"main.py\"<\/span>, line 4<\/span>, in<\/span> <module>\n    tax_amount = price * tax \/ 100<\/span>\nTypeError: can't multiply sequence by non-int of type '<\/span>str'<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Since the input values are strings, you cannot apply the multiply operator.<\/p>\n\n\n\n
To solve this issue, you need to convert the strings to numbers before performing calculations.<\/p>\n\n\n\n
To convert a string to a number, you use the int()<\/code> function. More precisely, the int()<\/code> function converts a string to an integer.<\/p>\n\n\n\n
The following example uses the int()<\/code> function to convert the input strings to numbers:<\/p>\n\n\n
price = input('Enter the price ($):'<\/span>)\ntax = input('Enter the tax rate (%):'<\/span>)\n\ntax_amount = int(price) * int(tax) \/ 100<\/span>\nprint(f'The tax amount is ${tax_amount}<\/span>'<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
If you run the program, and enter some values, you’ll see that it works correctly:<\/p>\n\n\n
Enter the price ($):\n100<\/span>\nEnter the tax rate (%):\n10<\/span>\nThe tax amount is<\/span> $10.0<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Other type conversion functions #<\/a><\/h2>\n\n\n\n
Besides the int(str)<\/code> functions, Python supports other type conversion functions. The following shows the most important ones for now:<\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n
However, the input()<\/code> function returns a string<\/a>, not an integer<\/a>. <\/p>\n\n\n\n
If you enter a value, for example, a number<\/a>, the program will display that value back:<\/p>\n\n\n
Try it<\/a><\/p>\n\n\n\n