遍历字典中的列表

Question

我是 Python 的新手，我希望在字典中的列表中遍历字典（我知道这很混乱）。

my_dict = {"John": [{"class": "math", "score": 100, "year": 2014}, {"class": "english", "score": 85, "year": 2015}], 
"Timmy": [{"class": "math", "score": 87, "year": 2014}, {"class": "english", "score": 91, "year": 2015}], 
"Sally":[{"class": "math", "score": 95, "year": 2014}]}

我需要创建一个包含学生姓名及其综合分数的新字典（Sally 只有一个分数）。

输出如下：

new_dict = {"John": 185, "Timmy": 178, "Sally": 95}

如有任何帮助或指导，我们将不胜感激！

Answer 1

使用字典理解：

{k: sum(x['score'] for x in v) for k, v in my_dict.items()}

代码:

my_dict = {"John": [{"class": "math", "score": 100, "year": 2014}, {"class": "english", "score": 85, "year": 2015}], 
"Timmy": [{"class": "math", "score": 87, "year": 2014}, {"class": "english", "score": 91, "year": 2015}], 
"Sally":[{"class": "math", "score": 95, "year": 2014}]}

new_dict = {k: sum(x['score'] for x in v) for k, v in my_dict.items()}
# {'John': 185, 'Timmy': 178, 'Sally': 95}

Answer 2

我试着写一个程序来解决这个问题。

score_dict = {}
for name in my_dict:
    score_dict[name] = 0
    class_items = my_dict[name]
    for class_item in class_items:
        score_dict[name] += class_item['score']

print score_dict

遍历字典中的列表

Iterate over list inside dictionary

python

dictionary

list-comprehension

list

dictionary-comprehension