Question

我正在尝试修改我构建的考试平均计算器，以便在结束while循环后计算总体平均值（示例下所需的输出代码）。我有功能代码，目前计算个别学生的平均值，但我无法找到计算整体平均值的方法。当前代码错误说出：TypeError：'float'对象不可迭代

numExams = int(input("How many exam grades does each student have? "))
students = 0 
total = 0
moreGrades = "Y" 

while moreGrades == "Y" :
    print("Enter the exam grades: ")
    total = 0 
        for i in range(1, numExams + 1) :
            score = int(input("Exam %d: " % i))
            total = total + score

    average = total / numExams
    print("The average is %.2f" % average)

moreGrades = input("Enter exam grades for another student? (Y/N)")
moreGrades = moreGrades.upper()
students = students + 1
total = sum(average)
print("The overall average is: ", total/students)

示例所需输出：

How many exam grades does each student have? (2)
Enter the exam grades.

Exam 1: (40)
Exam 2: (40)
The average is 40.00

Enter exam grades for another student? (Y/N) Y
Enter the exam grades

Exam 1: 20
Exam 2: 60
The average is 40.00

Enter exam grades for another student? (Y/N) n
The overall average is 40.00

Answer 1

这是因为你正在尝试

total = sum(average)

您可以将average循环之外的while定义为

average = []

所以它是一个列表，您可以将while循环中的每个平均值附加到此列表中。请参阅sum。

的文档

Answer 2

您试图总结一个浮点数，这是不可能的：

>>> sum(40.00)
Traceback (most recent call last):
  File "<pyshell#0>", line 1, in <module>
    sum(40.00)
TypeError: 'float' object is not iterable

您的代码也有一些缩进错误，这是您的代码的工作版本：

numExams = int(input("How many exam grades does each student have? "))
students = 0 
total = 0
moreGrades = "Y"
average = [] # set average to an empty list

while moreGrades == "Y" :
    print("Enter the exam grades: ")
    total = 0 
    for i in range(1, numExams + 1) : # you have indentation error here
        score = int(input("Exam %d: " % i))
        total = total + score

    average.append(total / numExams)
    print("The average is %.2f" % average[-1])

    moreGrades = input("Enter exam grades for another student? (Y/N)")
    moreGrades = moreGrades.upper()
    students = students + 1
total = sum(average)
print("The overall average is: ", total/students)

代码输出：

How many exam grades does each student have? 2
Enter the exam grades: 
Exam 1: 40
Exam 2: 40
The average is 40.00
Enter exam grades for another student? (Y/N)Y
Enter the exam grades: 
Exam 1: 20
Exam 2: 60
The average is 40.00
Enter exam grades for another student? (Y/N)N
The overall average is:  40.0

修改平均值计算器 - Python

2 个答案: