从函数

Question

我是一个相对新手，我正在努力帮助自己更好地理解功能。我为自己创造了一个练习

写一个简单的程序：

1. 问3个简单的Qs
2. 根据用户输入（每个Q响应由3个独特功能中的一个确定）响应每个Q
3. 将这些答案放在最后的简单摘要句中

我正在使用一个功能作为主'控制器' - ＆gt;的问题（）

我想调用问题（），然后从内部调用其他3个函数。我有一种感觉，我的函数需要参数 - 但我不确定（我已经尝试在各种函数中添加参数 - 但是已经完全卡住了 - 返回错误（请参见下文））

我的代码：

def naming(): # function to respond to name as per user input 
    if in_name == 'David':
        print 'That\'s a cool name!!'
    elif in_name == 'Jane':
        print 'That\'s a great name!!'
    else:
        print 'That\'s an OK name!!!'

def age(): # function to respond to age as per user input 
    if in_age > 60:
        print 'That\'s old!!'
    elif in_age < 15:
        print 'That\'s young!!'
    else:
        print 'That\'s neither young nor old!!'

def loc(): # function to respond to location as per user input 
    if in_loc == 'London':
        print 'London is a big city!!'
    elif in_loc == 'Manchester':
        print 'Manchester is a wonderful place!!'
    else:
        print 'That sounds OK!!'


def questions(): #function to own the whole process (name + age + loc)
    in_name = raw_input('What is your name? -->')
    naming()
    in_age = input('How old are you? -->')
    age()
    in_loc = raw_input('Where do you live? -->')
    loc()
    print 'Your name is',in_name,', you are' ,in_age , 'years old and you live in' , in_loc,'.'

questions()

我猜在主要的 questions（）函数中 - 我需要在命名/ age / loc 函数中提供某种形式的指令或参数

非常感谢这里的一些帮助！是的 - 这里有一些其他类似的线程 - 但我已经读过它们，没有一个对我有意义。 理想情况下 - 对我来说最有用的事情是，如果一些好的撒玛利亚人可以花3到4分钟来编辑我的代码以便正确操作。

提前致谢！

PS - 这是我得到的错误的屏幕截图

Answer 1

函数questions()中的变量不为其他函数所知（或者它们的范围仅限于questions()函数），这就是为什么你得到错误，没有定义

def naming(in_name): # function to respond to name as per user input 
    if in_name == 'David':
        print 'That\'s a cool name!!'
    elif in_name == 'Jane':
        print 'That\'s a great name!!'
    else:
        print 'That\'s an OK name!!!'

def age(in_age): # function to respond to age as per user input 
    if in_age > 60:
        print 'That\'s old!!'
    elif in_age < 15:
        print 'That\'s young!!'
    else:
        print 'That\'s neither young nor old!!'

def loc(in_loc): # function to respond to location as per user input 
    if in_loc == 'London':
        print 'London is a big city!!'
    elif in_loc == 'Manchester':
        print 'Manchester is a wonderful place!!'
    else:
        print 'That sounds OK!!'


def questions(): #function to own the whole process (name + age + loc)
    in_name = raw_input('What is your name? -->')
    naming(in_name)
    in_age = input('How old are you? -->')
    age(in_age)
    in_loc = raw_input('Where do you live? -->')
    loc(in_loc)
    print 'Your name is',in_name,', you are' ,in_age , 'years old and you live in' , in_loc,'.'

questions()

Answer 2

更好的方法是将它们作为参数传递给函数。

def naming(in_name): # function to respond to name as per user input 
    if in_name == 'David':
        print 'That\'s a cool name!!'
    elif in_name == 'Jane':
        print 'That\'s a great name!!'
    else:
        print 'That\'s an OK name!!!'

def questions(): #function to own the whole process (name + age + loc)
    in_name = raw_input('What is your name? -->')
    naming(in_name)

再次变量in_age，默认情况下需要转换为int raw_input string格式。

in_age = input('How old are you? -->')
age(int(in_age))

Answer 3

在函数内定义的变量是该函数的本地变量。它可以从定义它的位置访问，直到函数结束，并且只要函数正在执行就存在。

1. 您可以将值作为参数传递给其他函数

   def naming(in_name): # function to respond to name as per user input 
       if in_name == 'David':
           print 'That\'s a cool name!!'
       elif in_name == 'Jane':
           print 'That\'s a great name!!'
       else:
           print 'That\'s an OK name!!!'
   
   def age(in_age): # function to respond to age as per user input 
       if in_age > 60:
           print 'That\'s old!!'
       elif in_age < 15:
           print 'That\'s young!!'
       else:
           print 'That\'s neither young nor old!!'
   
   def loc(in_loc): # function to respond to location as per user input 
       if in_loc == 'London':
           print 'London is a big city!!'
       elif in_loc == 'Manchester':
           print 'Manchester is a wonderful place!!'
       else:
           print 'That sounds OK!!'
   
   
   def questions(): #function to own the whole process (name + age + loc)
       in_name = raw_input('What is your name? -->')
       naming(in_name)
       in_age = input('How old are you? -->')
       age(in_age)
       in_loc = raw_input('Where do you live? -->')
       loc(in_loc)
       print 'Your name is',in_name,', you are' ,in_age , 'years old and you live in' , in_loc,'.'
   
   questions()
   

2. 否则您可以将变量定义为全局，因此您不必将其作为参数传递。（建议不要使用此方法）

   def naming(): # function to respond to name as per user input 
       if in_name == 'David':
           print 'That\'s a cool name!!'
       elif in_name == 'Jane':
           print 'That\'s a great name!!'
       else:
           print 'That\'s an OK name!!!'
   
   def age(): # function to respond to age as per user input 
       if in_age > 60:
           print 'That\'s old!!'
       elif in_age < 15:
           print 'That\'s young!!'
       else:
           print 'That\'s neither young nor old!!'
   
   def loc(): # function to respond to location as per user input 
       if in_loc == 'London':
           print 'London is a big city!!'
       elif in_loc == 'Manchester':
           print 'Manchester is a wonderful place!!'
       else:
           print 'That sounds OK!!'
   
   
   def questions(): #function to own the whole process (name + age + loc)
       global in_name, in_age, in_loc
       in_name = raw_input('What is your name? -->')
       naming()
       in_age = input('How old are you? -->')
       age()
       in_loc = raw_input('Where do you live? -->')
       loc()
       print 'Your name is',in_name,', you are' ,in_age , 'years old and you live in' , in_loc,'.'
   
   questions()