The code says variable referenced before assignment?

Question

I'm getting this error from the code, "UnboundLocalError: local variable 'lowest' referenced before assignment". Why am I getting this? What does 'referenced before assignment' in this case really mean? Because I think that I assign the variable 'lowest' only after 'scores' variable is defined. Any help would be appreciated.

def main():
 scores = get_score()
 total = get_total(scores)
 lowest -= min(scores)
 average = total / (len(scores) - 1)
 print('The average, with the lowest score dropped is:', average)
def get_score():
 test_scores = []
 again = 'y'
 while again == 'y':
 value = float(input('Enter a test score: '))
 test_scores.append(value)
 print('Do you want to add another score? ')
 again = input('y = yes, anything else = no: ')
 print()
 return test_scores
def get_total(value_list):
 total = 0.0
 for num in value_list:
 total += num
 return total
main()

Answer 1

You're using -=, which requires a starting value. But you don't provide a starting value. In context it looks like you meant to use = instead.

Answer 2

That's because in main() you are saying

lowest -= min(scores)

which is essentially lowest = lowest - min(scores). Since you don't have lowest set previously, you'll get that error

• shanglawt: Thanks for the help. I either didn't see it or should go to my bed now. :)

Answer 3

Your lowest variable is not defined. You use "lowest -= min(scores)" which means subtract min(scores) from lowest, but lowest doesn't exist yet. Based on the name of the variable I'm guessing you want to do:

def main():
 scores = get_score()
 total = get_total(scores)
 lowest = min(scores)
 average = total / (len(scores) - 1)
 print('The average, with the lowest score dropped is:', average)