UnboundLocalError: local variable 'divide' referenced before assignment

Question

This program is designed to be fed a number and generate all of it's prime factors. I had this working without using any functions earlier, but now I am trying to implement them to get more functionality in my program.

divide = 2
factors = []

def nextNumber():
    userInput = input("enter a number to generate factors:\n") #
    number = int(userInput) 

    half = (number / 2) 
    halfFixed = int(half) 

    for x in range (0, halfFixed): # make second arg half of user number 
        result = number % divide

        if result == 0:
            factors.append(divide)

        divide +=1

nextNumber()
print (factors)

When I try to run it, the input command is read and I can input a number but as soon as I do I get the error, "UnboundLocalError: local variable 'divide' referenced before assignment" Any help at all would be great thanks.

Look at some of the questions on the right. – devnull Apr 17 '14 at 18:03 — devnull, Apr 17 '14 at 18:03

score 0 · Accepted Answer · answered Apr 17 '14 at 18:03

You are assigning to divide in your function, making it a local variable:

divide +=1

Any other use of divide before it is first assigned a value will then raise the UnboundLocal exception.

If you meant it to be a global, tell Python so with the global keyword:

def nextNumber():
    global divide

    userInput = input("enter a number to generate factors:\n") #
    number = int(userInput) 

    half = (number / 2) 
    halfFixed = int(half) 

    for x in range (0, halfFixed): # make second arg half of user number 
        result = number % divide

        if result == 0:
            factors.append(divide)

        divide +=1

That's got it working, thanks a lot and sorry if this as a repeated question, I am kinda new to this site. — Benjamin Cox, Apr 18 '14 at 00:09

UnboundLocalError: local variable 'divide' referenced before assignment

1 Answers1