全局名称没有被定义的错误

Question

我的代码：

import sys 
import time 
import random 


def main(): 
    print('***TEST**** Grad School Multiplier=',gradschoolmultiplier,'***TEST***') 
    x=gradschoolmultiplier*50000 
    print('Your salary in dollars, $',x) 

def start():  
    gradschool=input('Do you intend to go to Graduate School? ') 
    print('') 
    time.sleep(2) 
    if gradschool=='yes':print('That is a fantastic if expensive decision.') 
    elif gradschool=='Yes':print('That is a fantastic if expensive decision.') 
    elif gradschool=='Y':print('That is a fantastic if expensive decision.') 
    elif gradschool=='y':print('That is a fantastic if expensive decision.') 
    elif gradschool=='YES':print('That is a fantastic if expensive decision.') 
    else:print('No? Well, then it\'s off to work to pay back those student loans.') 
    print('') 
    if gradschool=='yes':g1=3 
    elif gradschool=='Yes':g1=3 
    elif gradschool=='Y':g1=3 
    elif gradschool=='y':g1=3 
    elif gradschool=='YES':g1=3 
    else:g1=1 
    g=random.randrange(1, 3) 
    if g==1:gradschoolmultiplier=1 
    else:gradschoolmultiplier=g1*g/2 
    time.sleep(2) 
    main() 

start() 

当然，我得到：

NameError: global name 'gradschoolmultiplier' is not defined 

我不是足够聪明，了解这个问题的答案为别人着想。有人会用傻瓜的话来解释答案吗？谢谢！

Answer 1

gradschoolmultiplier不在main()的范围内，它只存在于start()。

你可以将它传递给main。

变革的呼吁主要是main(gradschoolmultiplier)

变化def main()到def main(gradschoolmultiplier):

Information on python scoping

Answer 2

事实上，正如@丹说，范围界定问题。您可以使用global变量。

我的一些在你的代码的其他建议：

import sys 
import time 
import random 


def print_salary(): 
    print('***TEST**** Grad School Multiplier=',gradschoolmultiplier,'***TEST***') 
    x = gradschoolmultiplier*50000 
    print('Your salary in dollars, $',x) 

def main():  
    gradschool=input('Do you intend to go to Graduate School? ') 
    print('') 
    time.sleep(2) 

    if gradschool.lower() in {'yes', 'y'}: 
     print('That is a fantastic if expensive decision.') 
     g1 = 3 
    else: 
     print('No? Well, then it\'s off to work to pay back those student loans.') 
     g1 = 1 
    print('') 

    g = random.randrange(1, 3) 
    global gradschoolmultiplier 
    if g == 1: 
     gradschoolmultiplier = 1 
    else: 
     gradschoolmultiplier = g1 * g/2 
    time.sleep(2) 
    print_salary() 

if __name__ == '__main__': 
    main() 

您应该结合一些if报表，使其更简单。

哦，我们有着同样的想法@jonrsharpe

快速改善由@Nils的建议