找出嵌套字典中的值的总和并返回最大的键

Question

my_dict = {"student1": {"subject1": 100,"subject2":80, "subject3": 70},
           "student2": {"subject1": 500,"subject2":30, "subject3": 600}}

需要找出哪个学生的总分最高？

Answer 1

您可以使用字典理解来获取每个学生的分数总和。 然后，您可以使用max()找到总分最高的学生：

data = {"student1": {"subject1": 100,"subject2":80, "subject3": 70},
           "student2": {"subject1": 500,"subject2":30, "subject3": 600}}

totals = {student_id: sum(scores.values()) for student_id, scores in data.items()}
print(totals) # Prints {'student1': 250, 'student2': 1130}.

# Each element in .items() is a tuple with the student id as the first element,
# and their score as the second element.
# The key argument has us find the tuple with the maximum score.
top_scorer, top_score = max(totals.items(), key=lambda x: x[1])
print(top_scorer) # Prints student2.
print(top_score) # Prints 1130.

Answer 2

计算两个学生的最高分如下：

x = [sum(my_dict[i].values()) for i in my_dict.keys()]

然后打印得分最高的学生的姓名，如下所示：

if x[0] > x[1]:
    print("Student 1 has highest marks: ", x[0])
else:
    print("Student 2 has highest marks: ", x[1])

Answer 3

做就是了：

max(my_dict, key=lambda x:sum(my_dict[x][i] for i in my_dict[x]))


'student2'

Answer 4

如果您要处理大量数据，最好将其转换为更有用的数据类型，例如

df= pd.DataFrame.from_dict(my_dict, orient = 'index')

那么你可以做

df.sum(axis=1).sort_values(ascending = False).index[0]

或者

sums = df.sum(axis=1)
max(sums.index, key = lambda x: sums[x])