加权平均

Question

以下代码从用户那里获得了他上学期所学课程的某些成绩及其权重。用户完成操作后，他将输入“完成”而不是成绩。 我需要完成一个计算加权平均值的代码，并将其存储在四舍五入到百分之一的变量res中。

weighted average = sum(grade*points)/sum(points)

这是我到目前为止尝试过的：

    grade = input("enter your grade: ")
    points = input("enter the points: ")
    #innitialise the variables before while loop:
    
sum_grade = 0
    sum_points = 0

    #write a while loop that terminates when the user enters "done" to grade variable

    #calculate the grade to variable res in this format XX.XX

    while grade != "done":
        sum_grade += int(grade)
        sum_points += int(points)
        grade = input("enter your grade: ")
        points = input("enter the points: ")
        continue
        else:
        break
        
    res = sum_grade*sum_points / sum_points

    res ="%.2f"%float

非常感谢您：-）

Answer 1

您拥有正确的作品。您只需要按正确的顺序放置它们即可。

尝试以下代码：

sum_grade = 0
sum_points = 0
while True:
    grade = input("enter your grade: ")
    if grade == "done": break  # done
    points = int(input("enter the points: "))
    grade = int(grade)
    sum_grade += grade * points
    sum_points += points
    
res = sum_grade / sum_points

res ="%.2f"%res

print(res)

输出

enter your grade: 10
enter the points: 10
enter your grade: 50
enter the points: 1
enter your grade: done
13.64

Answer 2

您可以按以下方式使用Numpy：

import numpy as np

np.average(sum_grade, axis=1, weights=sum_points)

或通过如下方式修改代码：

sum_grade += int(grade*points)

和

res = sum_grade / sum_points