Python 3.5.3 KeyError: 0 returned from random.choice()

Question

here's my code:

fList = {7:7, 9:9}

def checkList():
    if not None in fList:
        print(fList)
        fL = random.choice(fList)
        ttt[fL] = computerLetter
        del fList[fL]
        print(fL)
        print(ttt)
        print(fList)

Python throws me this error:

{9: 9, 7: 7}
Traceback (most recent call last):
  File "/home/jason/Desktop/Programming/Python3_5/TestCode.py", line 35,     in <module>
    checkList()
  File "/home/jason/Desktop/Programming/Python3_5/TestCode.py", line 22, in checkList
    fL = random.choice(fList)
  File "/usr/lib/python3.5/random.py", line 265, in choice
    return seq[i]
KeyError: 0

This was working fine when there were move key:value pairs in the dictionary. I'm having trouble understanding whats wrong. Thank you in advance for your time and attention.

EarthDragon · Accepted Answer · 2017-07-26 05:14:42Z

3

From looking at your code it seems you expect random.choice to choose a key from you dictionary, so what you need to do is:

random.choice(list(fList.keys()))

BTW, I don't think you are using you conditional (if) properly. Currently it means that it will be executed only if fList doesn't have a key None (i.e. if your list was fList = {7:7, 9:9, None:5} it wouldn't execute). What I think you meant is if fList is not None, this means that it will only execute if it is defined

answered Jul 26, 2017 at 5:14

EarthDragon

7554 silver badges14 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Webmatt96 Over a year ago

Thank you. I want to run that if statement as long as the dictionary isn't empty. In your opinion what would be the best way of doing that?

EarthDragon Over a year ago

The Pythonic way is to write if fList which evaluates to True when there are values inside the dictionary and False when it is empty. Since you're using a dictionary, why are you calling it a fList?

Webmatt96 Over a year ago

No real reason. I just decided on a name.

Collectives™ on Stack Overflow

Python 3.5.3 KeyError: 0 returned from random.choice()

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related