Printing the return value of a function in python?

Question

I don't really understand what's wrong with my snippet here, it looks pretty simple but the compiler is returning an error to me.

choice = input("Enter a number: ")

def fact(num):
    if(num == 0):
        return 1
    return num * fact(num-1)

factorial = fact(choice)
print("The factorial of %d is %d." % (choice, factorial))

The function works fine, it's just something about setting the return to a variable, or possibly an issue in my print() statement. I'm just coding some random things to help me understand python syntax better.
Edit: the error

Enter a number: 3
Traceback (most recent call last):
  File "practice.py", line 10, in <module>
    factorial = fact(choice)
  File "practice.py", line 8, in fact
    return num * fact(num-1)
TypeError: unsupported operand type(s) for -: 'str' and 'int'

`choice = float(input("Enter a number: "))` or `int` instead of `float` — Trenton McKinney, Jul 16 '20 at 02:28
Python version matters on this question. Are you using python 2.x or 3.x? And notice that last entry in the traceback - its failing on the return from the function. — tdelaney, Jul 16 '20 at 02:33

Unmitigated · Accepted Answer · 2020-07-16T02:32:36.547

4

input returns a string which you need to convert to an int.

choice = int(input("Enter a number: "))

Demo

Your example works in Python 2, as input would try to assume the type of the entered value.

edited Jul 16 '20 at 02:32

answered Jul 16 '20 at 02:28

Unmitigated

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Oh I see, so input() doesn't automatically know the data type I entered after I entered it in the console? I have to manually set it if it isn't a string – cantcode4mylife Jul 16 '20 at 02:31
1

@c_help123 Python 2 tries to assume the type, but Python 3 no longer does that. – Unmitigated Jul 16 '20 at 02:32

Printing the return value of a function in python?

1 Answers1