Question

我有一个带有书籍信息的JSON文件。在原始文件中还有更多。

示例：

     [{"author": "Wes McKinney", "price": 53, "title": "Python for Data     Analysis", "publication_year": "2012", "topic": "programming"}, 
      {"author": "Joel Grus", "price": 66, "title": "Data Science from Scratch", "publication_year": "2015", "topic": "Python"}]

现在我想根据作者的姓氏对信息进行排序。我做了以下事情：

names = []
for a in jsondata:
names.append(str.split((a['author'])))

print (sorted(names))

然后我得到这样的信息：

[['Allan', 'Downey'], ['Allan', 'Downey']

我想知道是否有人可以给我一个提示/提示如何使用我如何根据作者的姓氏对所有信息进行排序。

Answer 1

您可以使用sorted()将lambda表达式排序为JSON结构：

lambda x: x["author"].split()[-1]
# split value of "author", key and sort based on the last word

无需显式迭代列表，并创建另一个列表来维护名称。

示例运行：

>>> my_json = [
        {"author": "Wes McKinney", "price": 53, "title": "Python for Data     Analysis", "publication_year": "2012", "topic": "programming"},
        {"author": "Joel Grus", "price": 66, "title": "Data Science from Scratch", "publication_year": "2015", "topic": "Python"}
    ]

>>> sorted(my_json, key=lambda x: x["author"].split()[-1])
[{'topic': 'Python', 'price': 66, 'title': 'Data Science from Scratch', 'publication_year': '2015', 'author': 'Joel Grus'}, {'topic': 'programming', 'price': 53, 'title': 'Python for Data     Analysis', 'publication_year': '2012', 'author': 'Wes McKinney'}]

Answer 2

试试这个：

names = []
for a in jsondata:
    last_name = a["author"].split(" ")[1]
    names.append(last_name)

print(sorted(names))

如果您想要排序字典，可以这样做：

for a in sorted(jsondata, key=lambda x: x["author"].split(" ")[1]):
    # You can use dict any way you like. E.g.:
    print(a["title"] + " " + str(a["price"]))

Answer 3

您只需要使用适当的键函数对jsondata列表进行排序，该函数从与每个dict的“author”键关联的值中提取姓氏。

我使用了.rsplit方法，因此我们可以有效地处理拥有2个以上名字的suthors。 .rsplit(None, 1)将字符串从右侧分割为空格，使（最多）一个分割，返回包含（最多）两个元素的列表。姓氏将是该列表的最后一个元素。如果您希望“Guido Van Rossum”的姓氏为“Van Rossum”，那么您需要使用不同的分割策略。

import json

jsondata = [
    {
        "author": "Wes McKinney", "price": 53, 
        "title": "Python for Data     Analysis", 
        "publication_year": "2012", "topic": "programming"
    },
    {
        "author": "Joel Grus", "price": 66, 
        "title": "Data Science from Scratch", 
        "publication_year": "2015", "topic": "Python"
    },
    {
        "author": "One",
    },
    {
        "author": "Person With A Long Name",
    },
]

def last_name(d):
    return d["author"].rsplit(None, 1)[-1]

# Verify that `last_name` does what we want
for d in jsondata:
    print(last_name(d))

jsondata.sort(key=last_name)

print(json.dumps(jsondata, indent=4))

<强>输出

McKinney
Grus
One
Name
[
    {
        "title": "Data Science from Scratch",
        "author": "Joel Grus",
        "topic": "Python",
        "publication_year": "2015",
        "price": 66
    },
    {
        "title": "Python for Data     Analysis",
        "author": "Wes McKinney",
        "topic": "programming",
        "publication_year": "2012",
        "price": 53
    },
    {
        "author": "Person With A Long Name"
    },
    {
        "author": "One"
    }
]

使用str.split

3 个答案: