Python的 - 合併字典添加重複鍵

Question

的值我需要合併了一系列的字典：

dict1 = {u'electronica ': 12.0, u'art rock ': 14.0, u'chillout ': 12.0, u'genius ': 14.0, u'trip-hop ': 11.0, u'psychedelic ': 12.0, u'indie pop ': 11.0, u'ambient ': 12.0, u'indie rock ': 15.0, u'post-rock ': 11.0, u'alternative rock ': 15.0, u'seen live ': 12.0, u'melancholic ': 14.0, u'Awesome ': 15.0, u'radiohead ': 19.0, u'emo ': 10.0, u'rock ': 16.0, u'indie ': 13.0, u'90s ': 5.0, u'pop ': 12.0, u'britpop ': 13.0, u'british ': 17.0, u'classic rock ': 12.0, u'better than radiohead ': 12.0, u'overrated ': 12.0, u'alternative ': 14.0, u'Progressive ': 13.0, u's ': 7.0, u'Favorite ': 12.0, u'electronic ': 13.0, u'Experimental Rock ': 13.0, u'beautiful ': 14.0, u'melancholy ': 14.0, u'idm ': 12.0, u'Progressive rock ': 12.0, u'favorites ': 12.0, u'english ': 12.0, u'male vocalists ': 13.0, u'experimental ': 12.0, u'UK ': 14.0} 
dict2 = {u'west coast': 26.0, u'hip hop': 24.0, u'rap': 19.0, u'gansta rap': 24.0} 
dict3 = {u'hip hop': 26.0, u'west coast': 28.0, u'rap': 21.0, u'gansta rap': 26.0} 
dict4 = {u'electronica ': 53.0, u'art rock ': 55.0, u'chillout ': 53.0, u'90s ': 5.0, u'trip-hop ': 52.0, u'psychedelic ': 53.0, u'ambient ': 53.0, u'Awesome ': 56.0, u'post-rock ': 52.0, u'alternative rock ': 56.0, u'seen live ': 53.0, u'melancholic ': 55.0, u'indie rock ': 56.0, u'melancholy ': 55.0, u'male vocalists ': 54.0, u'alternative ': 55.0, u'rock ': 57.0, u'indie ': 54.0, u'genius ': 55.0, u'pop ': 53.0, u'britpop ': 54.0, u'british ': 58.0, u'classic rock ': 53.0, u'better than radiohead ': 53.0, u'overrated ': 53.0, u'emo ': 51.0, u'Progressive ': 54.0, u's ': 48.0, u'Favorite ': 53.0, u'electronic ': 54.0, u'Experimental Rock ': 54.0, u'beautiful ': 55.0, u'radiohead ': 60.0, u'idm ': 53.0, u'Progressive rock ': 53.0, u'favorites ': 53.0, u'english ': 53.0, u'indie pop ': 52.0, u'experimental ': 53.0, u'UK ': 55.0} 

我可以使用此功能可以這樣做：

def merge_dicts(*dict_args): 

    result = {} 
    for dictionary in dict_args: 
     result.update(dictionary) 
    return result 

但我會失去跟蹤重複keys（這在例子中經常發生）。

相反，我必須合併dicts加入重複keys的values，因爲values這裏有weights。

我該如何做到這一點？

Answer 1

我會用一個collections.Counter：

In [9]: ds = [dict1, dict2, dict3, dict4] 

In [10]: from collections import Counter 

In [11]: result = Counter() 

In [12]: for d in ds: 
    ...:  result.update(d) 
    ...: 

而結果：

In [13]: result 
Out[13]: 
Counter({'90s ': 10.0, 
     'Awesome ': 71.0, 
     'Experimental Rock ': 67.0, 
     'Favorite ': 65.0, 
     'Progressive ': 67.0, 
     'Progressive rock ': 65.0, 
     'UK ': 69.0, 
     'alternative ': 69.0, 
     'alternative rock ': 71.0, 
     'ambient ': 65.0, 
     'art rock ': 69.0, 
     'beautiful ': 69.0, 
     'better than radiohead ': 65.0, 
     'british ': 75.0, 
     'britpop ': 67.0, 
     'chillout ': 65.0, 
     'classic rock ': 65.0, 
     'electronic ': 67.0, 
     'electronica ': 65.0, 
     'emo ': 61.0, 
     'english ': 65.0, 
     'experimental ': 65.0, 
     'favorites ': 65.0, 
     'gansta rap': 50.0, 
     'genius ': 69.0, 
     'hip hop': 50.0, 
     'idm ': 65.0, 
     'indie ': 67.0, 
     'indie pop ': 63.0, 
     'indie rock ': 71.0, 
     'male vocalists ': 67.0, 
     'melancholic ': 69.0, 
     'melancholy ': 69.0, 
     'overrated ': 65.0, 
     'pop ': 65.0, 
     'post-rock ': 63.0, 
     'psychedelic ': 65.0, 
     'radiohead ': 79.0, 
     'rap': 40.0, 
     'rock ': 73.0, 
     's ': 55.0, 
     'seen live ': 65.0, 
     'trip-hop ': 63.0, 
     'west coast': 54.0}) 

另外，如果你不想使用Counter：

In [14]: result = {} 

In [15]: for d in ds: 
    ...:  for k in d: 
    ...:   result[k] = result.get(k, 0) + d[k] 
    ...: 

In [16]: result 
Out[16]: 
{'90s ': 10.0, 
'Awesome ': 71.0, 
'Experimental Rock ': 67.0, 
'Favorite ': 65.0, 
'Progressive ': 67.0, 
'Progressive rock ': 65.0, 
'UK ': 69.0, 
'alternative ': 69.0, 
'alternative rock ': 71.0, 
'ambient ': 65.0, 
'art rock ': 69.0, 
'beautiful ': 69.0, 
'better than radiohead ': 65.0, 
'british ': 75.0, 
'britpop ': 67.0, 
'chillout ': 65.0, 
'classic rock ': 65.0, 
'electronic ': 67.0, 
'electronica ': 65.0, 
'emo ': 61.0, 
'english ': 65.0, 
'experimental ': 65.0, 
'favorites ': 65.0, 
'gansta rap': 50.0, 
'genius ': 69.0, 
'hip hop': 50.0, 
'idm ': 65.0, 
'indie ': 67.0, 
'indie pop ': 63.0, 
'indie rock ': 71.0, 
'male vocalists ': 67.0, 
'melancholic ': 69.0, 
'melancholy ': 69.0, 
'overrated ': 65.0, 
'pop ': 65.0, 
'post-rock ': 63.0, 
'psychedelic ': 65.0, 
'radiohead ': 79.0, 
'rap': 40.0, 
'rock ': 73.0, 
's ': 55.0, 
'seen live ': 65.0, 
'trip-hop ': 63.0, 
'west coast': 54.0} 

Answer 2

在Python字典你不允許給出重複密鑰。如果第二次給予同樣的密鑰，那麼系統w用第二個值覆蓋第一個值。

一個解決方案是你需要創建值的列表。

例如：{鍵：值，值，值]}

您可以找到以下鏈接最好的例子。

List of values for duplicate keys in dictionary Python