类型错误：“函数”对象不可下标 Python

TypeError: 'function' object is not subscriptable Python

提问by Stephen de Riel

I got an assignment in my Python 1 class consisting of this:

我在 Python 1 课程中得到了一个作业，其中包括：

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You are a score keeper for 20 ice hockey players. Implement the code to keep track of their scores using a list. Program accepts integers as input and it is called YI_ScoreKeeper.py. Simulate a game by entering a good number of scores.

您是 20 名冰球运动员的记分员。实现代码以使用列表跟踪他们的分数。程序接受整数作为输入，它被称为 YI_ScoreKeeper.py。通过输入大量分数来模拟游戏。

Here are two pics. she gave(I don't have enough rep. to post them as images)

这是两张照片。她给了（我没有足够的代表将它们作为图片发布）

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So far, my code is this:

到目前为止，我的代码是这样的：

def scorekeeper():
    Scorekeeper = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
    return Scorekeeper

def addscore(Scorekeeper):
    Addscore = int(input("what player scored a goal?"))
    Addscore = Addscore - 1 
    (Scorekeeper[Addscore]) = ((Scorekeeper[Addscore]) + 1) 
    return Scorekeeper
def histogram(Scorekeeper):
    print("\nCreating a histogram from values: ")
    print("%s %10s %10s" %("Element", "Ranking", "Histogram"))
    for i in range(len(Scorekeeper)):
        print("%7d%5d %-s" % (i +1, Scorekeeper[i], "*" * Scorekeeper[i])) 
def main():
    Scorekeeper = scorekeeper()
    endgame = 'n'
    while endgame == 'n':
        Addscore = addscore(scorekeeper)
        endgame = input("Has the game ended? y/n")

    histogram(scorekeeper)

main()

///////////////////////////////////////////////////////////////////////////////////////// I keep on getting this error:

///////////////////////////////////////////////// ///////////////////////////////////// 我不断收到此错误：

Traceback (most recent call last):
  File "C:/Python34/scorekeeper.py", line 27, in <module>
    main()
  File "C:/Python34/scorekeeper.py", line 22, in main
    Addscore = addscore(scorekeeper)
  File "C:/Python34/scorekeeper.py", line 11, in addscore
    (Scorekeeper[Addscore]) = ((Scorekeeper[Addscore]) + 1)
TypeError: 'function' object is not subscriptable

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Help? I'm not sure what I'm doing wrong.

帮助？我不确定我做错了什么。

回答by Eithos

You made a small mistake here:

你在这里犯了一个小错误：

def main():
    Scorekeeper = scorekeeper()
    endgame = 'n'
    while endgame == 'n':
        addscore(Scorekeeper) # This was set to scorekeeper
        endgame = input("Has the game ended? y/n")

    histogram(Scorekeeper) # Here too

Rather than calling the addscorefunction with the Scorekeeperlist you'd already returned from scorekeeper(), you were just sending in the function scorekeeper.

而不是addscore使用Scorekeeper您已经从 返回的列表调用该函数scorekeeper()，您只是发送了该函数scorekeeper。

This is why you were getting the error message; you were expecting to modify the ScoreKeeperlist with the index syntax you used, but instead you had a function object. Hope this clears it up.

这就是您收到错误消息的原因；您希望ScoreKeeper使用您使用的索引语法修改列表，但您有一个函数对象。希望这能解决问题。

Edit:

编辑：

As pointed out by @KevinJ.Chase:

正如@KevinJ.Chase所指出的：

The Addscorein Addscore = addscore(scorekeeper)didn't change anything. In Python, references to objectsare passed in as function parameters. What this means is that the passed parameter (inside the function) is a new identifier binded to the same object. While the logic involved here is not that terribly important to understand when passing immutable objects like an Int, a Str(etc.), passing a listmeans the new identifier inside the function references the same mutable data (the list). In this case, that mutable data was modified inside the function call; so returning it was indeed unnecessary.

将Addscore在Addscore = addscore(scorekeeper)没有改变任何东西。在 Python 中，对对象的引用作为函数参数传入。这意味着传递的参数（在函数内部）是绑定到同一对象的新标识符。虽然在传递像 an Int、 a Str（等）这样的不可变对象时理解这里涉及的逻辑并不是那么重要，但传递 alist意味着函数内的新标识符引用相同的可变数据（list）。在这种情况下，可变数据在函数调用中被修改；所以返回它确实是不必要的。

回答by Padraic Cunningham

You are not calling the function to access the list:

您不是调用函数来访问列表：

(Scorekeeper()[Addscore]) = ((Scorekeeper()[Addscore]) + 1)

You also need to call the function in your loop:

您还需要在循环中调用该函数：

 for i in range(len(Scorekeeper())):
        print("%7d%5d %-s" % (i +1, Scorekeeper()[i], "*" * Scorekeeper()[i]))

But really you should just declare a list outside of the functions and just access the list directly and forget about using the functions:

但实际上，您应该只在函数之外声明一个列表，然后直接访问该列表而忘记使用这些函数：

scorekeeper = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

scorekeeper = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

You can change the histogram function yourself but this is an idea of how to write simpler more straight forward code:

您可以自己更改直方图函数，但这是如何编写更简单更直接的代码的想法：

def add_score():
    score = int(input("what player scored a goal?"))
    return score


def main():
    endgame = 'n'
    score_keeper = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
    while endgame == 'n':
        scorer = add_score()
        score_keeper[scorer] += 1
        endgame = input("Has the game ended? y/n")

When taking input and especially casting you should use a try/exceptto validate so I would add a second while loop in add_scorewith a try except.

当接受输入，尤其是强制转换时，你应该使用try/except来验证，所以我会添加第二个 while 循环add_score和 try except。