迭代字典值，這些列表值是用於創建新的字典列表的列表

Question

我有一個字典，其中包含鍵'Title'，'Author'，'Publication Year'，其值為列表：

book_dict= {'Titles': ['Double Play', 'Slow Burn', 'Altman Code'], 'Authors': ['Brown, Dan', 'Hannah, Kristin', 'Neri, Penelope'], 
'Publication Year': [2004, 2003, 2006]}

列表中每個條目的位置彼此對應，例如book_dict['Titles'][0]和book_dict['Authors'][0]是關於同一本書的信息。 （注意：這些是書籍和作者的實際名稱，但實際上並不相互對應）

我想創建一個包含這樣的字典的列表：

[{"Title":"Double Play","Author":"Brown, Dan", "Publication Year":2004}, 
{"Title":"Slow Burn","Author":"Hannah, Kristin", "Publication Year":2003},
{"Title":"Altman Code","Author":"Neri, Penelope'", "Publication Year":2006}]

到目前為止，我試過這個：

for i in range(30):
    for k,v in book_dict.items():
        print({k[i]:v[i]})

但我得到了這個：

{"Title":"Double Play"}
{"Author":"Brown, Dan"}
{"Publication Year":2004}
{"Title":"Slow Burn"}
{"Author":"Hannah, Kristin"}
{"Publication Year":2003}
{"Title":"Altman Code"}
{"Author":"Neri, Penelope"} 
{"Publication Year":2006}

加上IndexError: list index out of range

Answer 1

你將不得不在原始字典的值上使用一些zip變體：

>>> [{'Title': t, 'Author': a, 'Publication Year': y} for t, a, y in zip(book_dict['Titles'], book_dict['Authors'], book_dict['Publication Year'])]
[{'Title': 'Double Play', 'Author': 'Brown, Dan', 'Publication Year': 2004}, 
 {'Title': 'Slow Burn', 'Author': 'Hannah, Kristin', 'Publication Year': 2003}, 
 {'Title': 'Altman Code', 'Author': 'Neri, Penelope', 'P
ublication Year': 2006}]

您可以使用一些工具來使其更具可讀性：

from  operator import itemgetter

items = itemgetter('Titles', 'Authors', 'Publication Year')
[
    {'Title': t, 'Author': a, 'Publication Year': y} 
    for t, a, y in zip(*items(book_dict))
]
# [{'Title': 'Double Play', 'Author': 'Brown, Dan', 'Publication Year': 2004}, 
#  {'Title': 'Slow Burn', 'Author': 'Hannah, Kristin', 'Publication Year': 2003}, 
#  {'Title': 'Altman Code', 'Author': 'Neri, Penelope', 'Publication Year': 2006}]

Answer 2

不需要對密鑰進行硬編碼的通用方法是迭代dict的壓縮值並使用壓縮值壓縮dict鍵以使用dict構造函數構建子代碼：

[dict(zip(book_dict, t)) for t in zip(*book_dict.values())]

返回：

[{'Titles': 'Double Play', 'Authors': 'Brown, Dan', 'Publication Year': 2004},
 {'Titles': 'Slow Burn', 'Authors': 'Hannah, Kristin', 'Publication Year': 2003},
 {'Titles': 'Altman Code', 'Authors': 'Neri, Penelope', 'Publication Year': 2006}]

Answer 3

嘗試這個 ：

[{k : book_dict[k][j] for k in book_dict} for j in range(len(book_dict['Titles']))]

輸出 ：

[{'Titles': 'Double Play', 'Authors': 'Brown, Dan', 'Publication Year': 2004}, {'Titles': 'Slow Burn', 'Authors': 'Hannah, Kristin', 'Publication Year': 2003}, {'Titles': 'Altman Code', 'Authors': 'Neri, Penelope', 'Publication Year': 2006}]

Answer 4

您可以使用zip()以鎖步方式迭代多個列表，例如

result = []
for title, author, year in zip(book_dict['Titles'], book_dict['Authors'],     
book_dict['Publication Year']):
    result.append({'Title': title, 'Author': author, 'Year': year})

print result