条件が満たされるとループは終了しません

Question

ループを終了させるために関数を取得しようとしていますが、復帰句に達した時点でループを終了しようとしていますが、失敗します。 ダイレクトコード編集ではなく、説明がうまくいきます。

def Menu(): 
    UserMenu = True 
    print (""" 
     U.Create a Username 
     E.Run Exponential Calculator 
     Q.Exit/Quit 
     """) 
    while UserMenu not in ("U", "E", "Q"): 
     print("\n Error: Choice must be U, E or Q") 
    return UserMenu 

# Function designed to retrieve first name only from fullname entry. 
def get_first_name(name): 
    first=[""] 
    i = 0 
    while i < len(name) and name[i] !=" ": 
     first += name[i] 
     i += 1 
    return name[:i] 

# Function designed to retrieve first initial of last name or first initial of first name if only one name input. 
def get_last_initial(name): 
    j = len(name) - 1 
    while j >= 0 and name[j] !=" ": 
     j-=1 
    return name[j+1] 


# Function that generates username based upon user input. 
def get_username(): 
    name = raw_input("Please enter your Full Name: ") 
    username = get_first_name(name) + get_last_initial(name) 
    return username.lower() 



# Function to generate exponential numbers based upon usser input. 
def print_exponential(): 
    base = int(raw_input("Please select a base number: \n")) 
    power = int(raw_input("Please select a power number: \n")) 
    exponential = 1 
    while power>0: 
     exponential = exponential * base 
     print base 
     if power >1: 
      print "*", 
     power = power -1 
    return "=%d" % exponential 

print Menu() 
while UserMenu != "Q": 
    if UserMenu is "U": 
     UserMenu = raw_input("Please enter your Full Name: ") 
     print "your username is %s" % get_username() 
    else: 
     print print_exponential() 
    print Menu() 

これはプログラム全体です。役立ちますように！

Answer 1

あなたは、ループ内UserMenuの値を更新する必要がある、または他のループに入ることは、本質的に無限ループになります：ループ内で新しい入力を取得することにより

def Menu(): 
    UserMenu = raw_input(""" 
     U.Create a Username 
     E.Run Exponential Calculator 
     Q.Exit/Quit 
     """) 
    while UserMenu not in ("U", "E", "Q"): 
     UserMenu = raw_input("\n Error: Please input only U, E or Q:") 
    return UserMenu 


... 
all your other functions 
... 

user_choice = Menu() 
while user_choice != "Q": 
    if user_choice == "U": 
     print "your username is %s" % get_username() 
    else: 
     print_exponential() 
    user_choice = Menu() 

、会うことができるようになりますループを制御する基準。あなたが書いたループはそのまま印刷され、UserMenuを変更せずにチェックするので、ループは決して終了しません。

Answer 2

次のコードを使用して問題を解決することができました。

def Menu(): 
    result = raw_input (""" 
     U.Create a Username 
     E.Run Exponential Calculator 
     Q.Exit/Quit 
     """).upper() 
    while result not in ("U", "E", "Q"): 
     print("\n Error: Please input only U, E or Q:") 
     result = raw_input (""" 
     U.Create a Username 
     E.Run Exponential Calculator 
     Q.Exit/Quit 
     """).upper() 
    return result 


# Function designed to retrieve first name only from fullname entry. 
def get_first_name(full_name): 
    i = 0 
    while i < len(full_name) and full_name[i] !=" ": 
     i += 1 
    return full_name[:i] 

# Function designed to retrieve first initial of last name or first initial of first name if only one name input. 
def get_last_initial(full_name): 
    j = len(full_name) - 1 
    while j >= 0 and full_name[j] !=" ": 
     j-=1 
    return full_name[j+1] 


# Function that generates username based upon user input. 
def get_username(): 
    username = get_first_name(full_name) + get_last_initial(full_name) 
    return username.lower() 



# Function to generate exponential numbers based upon user input. 
def print_exponential(): 
    base = int(raw_input("Please select a base number: \n")) 
    power = int(raw_input("Please select a power number: \n")) 
    exponential = 1 
    while power>0: 
     exponential = exponential * base 
     print base 
     if power >1: 
      print "*", 
     power = power -1 
    return "=%d" % exponential 

choice = Menu() 
while choice != "Q": 
    if choice == "U": 
     full_name = raw_input("Please enter your Full Name:") 
     print "your username is %s" % get_username() 
    else: 
     print print_exponential() 
    choice = Menu()