Python字典-如何平均键，值对中的多个数字[重复]

Question

student = {'first_name': 'Bob', 'last_name': 'Barker',
               'assignments': [('assignment1', 75), ('assignment2', 100), ('assignment3', 47), ('assignment4', 97)]}
    
    
def average_grade(student):
    grade = sum(student['assignments']) / len(student['assignments'])
    print(grade)
    
average_grade(student)

我正在尝试平均分配的值，但我完全卡住了！

Answer 1

问题是您正在尝试对作业求和，即元组，而不仅仅是作业的成绩。试试这个：

student = {'id': 1, 'first_name': 'Bob', 'last_name': 'Barker',
           'assignments': [('assignment1', 0), ('assignment2', 2), ('assignment3', 4)]}


def average_grade(student):
    assignment_grades = [assignment[1] for assignment in student['assignments']]
    grade = sum(assignment_grades) / len(student['assignments'])
    print(grade)


average_grade(student)

Answer 2

问题是您尝试对元组求和，而不是对成绩的整数值求和。

一个可能的解决方案：

def average_grade(student):
  sum_of_assignments = sum(assignment[1] for assignment in student['assignments'])
  num_of_assignments = len(student['assignments'])
  grade = sum_of_assignments / num_of_assignments
  print(grade)

average_grade(student)
# 2.0