将字符串除以整数以获得 GPA 计算

Question

我正在使用 Python 并正在编写一个程序，用户可以在其中输入他们想要计算的课程数量。然后程序应该获取附加的项目（字符串），然后将它们除以他们想要的课程数量，换句话说，总数（整数）。我似乎无法找到正确实施此功能的方法，有什么帮助吗？问题在于 If value = 1。

if (value == 1):
    selection = int(input("How many classses would you like to include?\n"))
    for i in range (0,selection):
        print("What is the grade of the class?")
        item = (input())
        grades.append(item)
        GPA_list = [sum(item)/selection for i in grades]
        print(GPA_list)
    

Answer 1

您可以使用mean 来简化这个过程，它会为您进行求和和除法：

>>> from statistics import mean
>>> print(mean(
...     float(input(
...         "What is the grade of the class?\n"
...     )) for _ in range(int(input(
...         "How many classes would you like to include?\n"
...     )))
... ))
How many classes would you like to include?
5
What is the grade of the class?
4
What is the grade of the class?
3
What is the grade of the class?
4
What is the grade of the class?
2
What is the grade of the class?
4
3.4

要修复现有代码，您需要做的就是确保将 item 转换为浮点数，然后在 grades 而不是每个 item 上调用 sum：

grades = []
selection = int(input("How many classses would you like to include?\n"))
for i in range(0, selection):
    print("What is the grade of the class?")
    item = float(input())
    grades.append(item)
    GPA_list = sum(grades) / selection
    print(GPA_list)

请注意，您的代码会在循环中的每个步骤打印平均值的一小部分，直到最终在最后一次迭代中打印出正确的结果；如果您也想解决此问题，请取消缩进最后两行。