TypeError：只能在 Python 中连接元组（不是“int”）

TypeError: can only concatenate tuple (not "int") in Python

提问by sammojohn

I am going to need your help with this constant tuple error I keep getting. Seems that it is a common mathematical error that many have. I have read almost every instance of TypeError including 'not int', 'not list', 'not float' etc. Yet I have failed to figure out why I get it.

我需要你的帮助来解决这个不断出现的元组错误。似乎这是许多人常见的数学错误。我已经阅读了几乎所有 TypeError 实例，包括“not int”、“not list”、“not float”等。但我一直没有弄清楚为什么我会得到它。

I have written the below code that allows you to enter the sum of random number and in the end it calculates your success ratio. So I have a counter "right=right+1" to count my correct answers. Seems as if Python doesn't like that.

我编写了以下代码，允许您输入随机数的总和，并最终计算您的成功率。所以我有一个计数器“right=right+1”来计算我的正确答案。似乎 Python 不喜欢那样。

Here is what I have written:

这是我写的：

import random 
#the main function
def main():
    counter, studentName, averageRight, right, answer, number1, number2 = declareVariables() 
    studentName = inputNames()

    while counter < 10:
        number1, number2 = getNumber()
        answer = getAnswer(number1, number2, answer)
        right = checkAnswer(number1, number2, answer, right)
        counter = counter + 1
    results(right, averageRight)
    displayInfo(studentName, right, averageRight)

def declareVariables():
    counter = 0
    studentName = 'NO NAME'
    averageRight = 0.0
    right = 0.0
    answer = 0.0
    number1 = 0
    number2 = 0
    return counter, studentName, averageRight, right, answer, number1, number2

def inputNames():
    studentName = raw_input('Enter Student Name: ')
    return studentName

def getNumber():
    number1 = random.randint(1, 500)
    number2 = random.randint(1, 500)
    return number1, number2

def getAnswer(number1, number2, answer):
    print 'What is the answer to the following equation'
    print number1
    print '+'
    print number2
    answer = input('What is the sum: ')
    return answer

def checkAnswer(number1, number2, answer, right):
    if answer == number1+number2:
        print 'Right'
        right = right + 1
    else:
        print 'Wrong'

    return right, answer

def results(right, averageRight):
    averageRight = right/10
    return averageRight



def displayInfo(studentName, right, averageRight):
    print 'Information for student: ',studentName
    print 'The number right: ',right
    print 'The average right is: ', averageRight

# calls main
main()

and I keep getting:

我不断得到：

Traceback (most recent call last):
  File "Lab7-4.py", line 70, in <module>
    main()
  File "Lab7-4.py", line 15, in main
    right = checkAnswer(number1, number2, answer, right)
  File "Lab7-4.py", line 52, in checkAnswer
    right = right + 1
TypeError: can only concatenate tuple (not "int") to tuple Press any key to continue . . .

采纳答案by Martijn Pieters

Your checkAnswer()function returns a tuple:

您的checkAnswer()函数返回一个元组：

def checkAnswer(number1, number2, answer, right):
    if answer == number1+number2:
        print 'Right'
        right = right + 1
    else:
        print 'Wrong'

    return right, answer

Here return right, answerreturns a tuple of two values. Note that it's the comma that makes that expression a tuple; parenthesis are optional in most contexts.

这里return right, answer返回一个包含两个值的元组。请注意，是逗号使该表达式成为元组；在大多数情况下，括号是可选的。

You assign this return value to right:

您将此返回值分配给right：

right = checkAnswer(number1, number2, answer, right)

making righta tuple here.

right在这里制作一个元组。

Then when you try to add 1to it again, the error occurs. You don't change answerwithin the function, so there is no point in returning the value here; remove it from the returnstatement:

然后当您再次尝试添加1时，就会出现错误。你不会answer在函数内改变，所以在这里返回值没有意义；从return语句中删除它：

def checkAnswer(number1, number2, answer, right):
    if answer == number1+number2:
        print 'Right'
        right = right + 1
    else:
        print 'Wrong'

    return right

回答by thefourtheye

right = checkAnswer(number1, number2, answer, right)

You are assigning what is returned by checkAnswer. But you are returning a tuple from it.

您正在分配checkAnswer. 但是您正在从中返回一个元组。

return right, answer

So, after the first iteration rightbecomes a tuple. And when it reaches

所以，在第一次迭代之后right就变成了一个元组。当它达到

right = right + 1

the second time, it fails to add an int to a tuple.

第二次，它无法将 int 添加到元组中。

回答by DevinLynch99

Try rightFloat = float(right[0] + 1)and just reference rightFloat. Just a workaround in case you get lazy.

尝试rightFloat = float(right[0] + 1)并参考rightFloat. 只是一个解决方法，以防你变懒。

回答by Mahmud Hasan

I don't think your averageRightgives the right result. So I fixed the code. I am using IDLE 3.5.2 so some syntax might seem little different (for example print()). So below is the code. You are welcome :)

我不认为你averageRight给出了正确的结果。所以我修复了代码。我使用的是 IDLE 3.5.2，所以有些语法可能看起来没什么不同（例如print()）。所以下面是代码。不客气 ：）

import random 
#the main function
def main():
    counter, studentName, averageRight, right, answer, number1, number2 = declareVariables() 
    studentName = inputNames()

    while counter < 10:
        number1, number2 = getNumber()
        answer = getAnswer(number1, number2, answer)
        right = checkAnswer(number1, number2, answer, right)
        counter = counter + 1

    A=results(right, averageRight)
    displayInfo(studentName, right, A)

def declareVariables():
    counter = 0
    studentName = 'NO NAME'
    averageRight = 0.0
    right = 0
    answer = 0
    number1 = 0
    number2 = 0
    return counter, studentName, averageRight, right, answer, number1, number2

def inputNames():
    studentName = input('Enter Student Name: ')
    return studentName

def getNumber():
    number1 = random.randint(1, 500)
    number2 = random.randint(1, 500)
    return number1, number2

def getAnswer(number1, number2, answer):
    print ('What is the answer to the following equation')
    print (number1)
    print ('+')
    print (number2)
    answer = int(input('What is the sum: ')) #input would be a int. without adding the int it would make answer a string instead of int. which was reason why it was giving 'wrong' 
    return answer

def checkAnswer(number1, number2, answer, right):
    if answer==number1+number2:
        print ('Right')
        right = right + 1
    else:
        print ('Wrong')

    return right

def results(right, averageRight):
    averageRight = right/10
    return averageRight



def displayInfo(studentName, right, A):
    print ('Information for student: ',studentName)
    print ('The number right: ',right)
    print ('The average right is: ', A)

# calls main
main()