使用不同的变量类型从Python字典中检索值

Question

在字典中如下：

dict = [{'author':'Joyce', 'novel': 'Dubliners'},
{'author':'Greene','novel':'The End of the Affair'},
{'author':'JD Salinger','novel':'Catcher in the Rye'}]

如何使用＆＃39;作者＆＃39;以理解的方式检索所有小说？作为键。

Answer 1

如果您正在寻找特定作者的所有书籍：

>>> author = 'Joyce'
>>> [d['novel'] for d in data if d['author'] == author]
['Dubliners']

所有小说：

>>> [d['novel'] for d in data]
['Dubliners', 'The End of the Affair', 'Catcher in the Rye']

Answer 2

你可以使用列表理解

[x["novel"] for x in dict if x["author"] == author_name]

获得所有小说：

[x["novel"] for x in dict]

Answer 3

我想这是预期的结果，但我不确定是否有一种简单的方法可以使用理解来做到这一点。

books = [{'author':'Joyce', 'novel': 'Dubliners'},
    {'author':'Greene','novel':'The End of the Affair'},
    {'author':'JD Salinger','novel':'Catcher in the Rye'}]

nbooks = {}
for book in books:
    author = book['author']
    novel = book['novel']
    nbooks.setdefault(author, []).append(novel)

print(nbooks['Joyce'])