编写嵌套代码时未绑定的本地错误

Question

我试图在我的python上调整子文件，但它一直向我显示先前引用的变量(Min_Alpha)上的unboundlocalerror。我很困惑，如果我运行alpha命令，我没有得到错误，虽然当我运行beta命令，我得到这个错误。如有任何帮助，不胜感激。

def main():

print("Welcome to the Beta Distribution Software")
print(" ")
playerschoice = input("Do you want to use this software ? Yes/No : ")
if (playerschoice == "yes" or playerschoice =="Yes" or playerschoice == "YES"):
Body_function_01()

else:
end_program()

def Body_function_01():

users_choice = input("What constant would you like to vary ? Alpha/Beta: ")
if (users_choice == "Alpha" or users_choice == "alpha"):
Max_Alpha = float(input("Enter the Maximum Alpha Value: "))
Min_Alpha = float(input("Enter the Minimum Alpha Value: "))
Alpha_increment = float(input("Enter Alpha Increment Value: "))
Beta_constant = float(input("Enter constant Beta value"))  
else:
Body_function_02() 

if (Min_Alpha >= 0):
print("Minimum Alpha value is within an acceptable range")
elif (Min_Alpha < 0):
print("Minimum value of alpha is too low ")
print ("Try again")
if ((Max_Alpha - Min_Alpha) > Alpha_increment):
print("The Alpha Increment is within an acceptable range")
elif ((Max_Alpha - Min_Alpha) < Alpha_increment):
print("The Alpha increment is too high")
print("Try again")
if (Max_Alpha > Min_Alpha):
print("The Maximum value of alpha is within an acceptable range")
elif (Max_Alpha < Min_Alpha):
print("The maximum value of alpha is too high")
print("Try again")




def Body_function_02():

users_choice = input("What constant would you like to vary ? Alpha/Beta: ")
if (users_choice == "Beta" or users_choice == "beta"):
Max_Beta = float(input("Enter the Maximum Beta Value: "))
Min_Beta = float(input("Enter the Minimum Beta Value: "))
Beta_increment = float(input("Enter Beta Increment Value: "))
Alpha_constraint = float(input("Enter constant Alpha value: "))

else:
print("Try again")

if (Min_Beta >= 0):
print("Minimum Beta value is within an acceptable range")
elif (Min_Beta < 0):
print("Minimum value of Beta is too low ")
print ("Try again")
if ((Max_Beta - Min_Beta) > Beta_increment):
print("The Beta Increment is within an acceptable range")
elif ((Max_Beta - Min_Beta) < Beta_increment):
print("The Beta increment is too high")
print("Try again")
if (Max_Beta > Min_Beta):
print("The Maximum value of Beta is within an acceptable range")
elif (Max_Beta < Min_Beta):
print("The maximum value of Beta is too high")
print("Try again")

def end_program():
print(" ")
input("Press any key to leave")
sys.exit()

main()   
Body_function_01()   
Body_function_02()
end_program().   

---------------------------------------------------------------------------
UnboundLocalError                         Traceback (most recent call last)
<ipython-input-25-c662d0a92b77> in <module>
111 
112 
--> 113 main()
114 Body_function_01()
115 Body_function_02()
<ipython-input-25-c662d0a92b77> in main()
16     playerschoice = input("Do you want to use this software ? Yes/No : ")
17     if (playerschoice == "yes" or playerschoice =="Yes" or playerschoice == "YES"):
---> 18         Body_function_01()
19 
20     else:
<ipython-input-25-c662d0a92b77> in Body_function_01()
33         Body_function_02()
34 
---> 35     if (Min_Alpha >= 0):
36         print("Minimum Alpha value is within an acceptable range")
37     elif (Min_Alpha < 0):
UnboundLocalError: local variable 'Min_Alpha' referenced before assignment

Answer 1

我认为问题是Min_Alpha在以下情况下被初始化:

users_choice = input("What constant would you like to vary ? Alpha/Beta: ")
if (users_choice == "Alpha" or users_choice == "alpha"):
Max_Alpha = float(input("Enter the Maximum Alpha Value: "))
Min_Alpha = float(input("Enter the Minimum Alpha Value: "))
Alpha_increment = float(input("Enter Alpha Increment Value: "))
Beta_constant = float(input("Enter constant Beta value"))  

只有当用户选择Alpha/Alpha时才会初始化。对于任何其他选择，变量将不会被初始化，并且当您将其与0进行比较时，它将是无界的。不确定预期的行为是什么，但我认为你应该在Body_function_01和Body_function_02函数的else情况下return。