TypeError：只能在 Python 中连接元组（不是“int”）

Question

我将需要您的帮助来解决我不断收到的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。但我无法弄清楚为什么会得到它。

我编写了下面的代码，允许您输入随机数的总和，最后它会计算您的成功率。所以我有一个计数器“right=right+1”来计算我的正确答案。好像 Python 不喜欢那样。

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()

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 . . .

Answer 1

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

这里return right, answer 返回两个值的元组。请注意，使该表达式成为元组的是逗号；在大多数情况下，括号是可选的。

您将此返回值分配给right：

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

在这里制作right 一个元组。

然后当您再次尝试添加1 时，就会出现错误。您不会在函数内更改answer，因此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

Answer 2

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

您正在分配 checkAnswer 返回的内容。但是您正在从中返回一个元组。

return right, answer

所以，在第一次迭代之后，right 变成了一个元组。当它到达

right = right + 1

第二次，它无法将 int 添加到元组中。

Answer 3

我认为您的 averageRight 没有给出正确的结果。所以我修复了代码。我使用的是 IDLE 3.5.2，因此某些语法可能看起来略有不同（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()

Answer 4

尝试rightFloat = float(right[0] + 1) 并仅引用rightFloat。只是一个解决方法，以防你变得懒惰。