A python program that reads numbers and stops when you enter 'done' using try and except

Question

I tried writing a program that reads numbers using a loop, evaluates the total numbers, prints it and stops when you type done using try and except.

initiator = True
myList = []

while initiator:
    try:
        userIn = int(input('Enter any number >>  '))
        myList.append(userIn)
        print(myList)

    except ValueError:
        if str(userIn):
            if userIn == 'done':
                pass
            average = eval(myList)
            print(average)
            initiator = False

        else:
            print('Wrong input!\nPlease try again')
            continue

And so what is your actual question? If this code isn't working as you want, you need to explain. Are you getting errors, or unexpected output? — John Gordon, Dec 13 '22 at 00:55
Stopping by to say - [don't use eval](https://stackoverflow.com/a/1832957/4935162). Not sure why it's in this code in the first place. Edit: okay, it doesn't do what you think it does. See Barmar's answer — Yarin_007, Dec 13 '22 at 00:59
It says: average = eval(myList) TypeError: eval() arg 1 must be a string, bytes or code object — Kimm Muna, Dec 13 '22 at 01:00

score 0 · Accepted Answer · answered Dec 13 '22 at 00:59

When int() raises an exception, it doesn't set userIn, so you can't compare userIn with done.

You should separate reading the input and callint int().

while True:
    try:
        userIn = input('Enter any number >>  ')
        num = int(userIn)
        myList.append(num)
        print(myList)

    except ValueError:
        if userIn == 'done':
            break
        else:
            print('Wrong input!\nPlease try again')

average = sum(myList) / len(myList)
print(average)

eval() is not the correct way to get the average of a list. Use sum() to add up the list elements, and divide by the length to get the average.

A python program that reads numbers and stops when you enter 'done' using try and except

1 Answers1