我有一個包含鍵的字典，同時該鍵包含某個整數串列。我想構建一個字典，將值顯示為鍵，而這個新字典的值將是包含先前值的先前鍵的串列。例如，我有：
turns
{'Monday_2022_03_14': [25, 17, 2, 32, 43, 40, 23, 7, 19, 16],
'Tuesday_2022_03_15': [33, 10, 16, 31, 25, 22, 43, 41, 21, 28, 3, 30, 29],
'Wednesday_2022_03_16': [19, 27, 40, 3, 9, 2, 14, 21, 44, 17],
'Thursday_2022_03_17': [16, 23, 1, 30, 29, 44, 5, 42, 27, 19],
'Friday_2022_03_18': [6, 17, 2, 29, 27, 41, 44, 5, 40, 42]}
例如，我想有：
{1:['Thursday_2022_03_17'],
2:['Monday_2022_03_14','Wednesday_2022_03_16','Friday_2022_03_18'],
3:['Tuesday_2022_03_15','Wednesday_2022_03_16],
...} #and so on
我嘗試在回圈中實作下一個解決方案（我在Get key by value in dictionary中找到了它），但后來我意識到這只能在只有一個值的鍵的字典中作業，而不是像我的串列：
list(turns.keys())[list(turns.values()).index(16)]
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
~\AppData\Local\Temp/ipykernel_19168/930684082.py in <module>
----> 1 list(turns.keys())[list(turns.values()).index(16)]
ValueError: 16 is not in list
如果你不提供回圈解決方案也沒關系，我可以實作它，但我需要幫助來按值獲取鍵名（如上面的行），但專注于串列而不是簡單值。
謝謝大家。
uj5u.com熱心網友回復：
一種方法是使用dict.setdefault和迭代串列：
out = {}
for k, lst in turns.items():
for v in lst:
out.setdefault(v, []).append(k)
然后，如果您希望字典按鍵排序，您可以使用sorted：
out = {k: out[k] for k in sorted(out)}
輸出：
{1: ['Thursday_2022_03_17'],
2: ['Monday_2022_03_14', 'Wednesday_2022_03_16', 'Friday_2022_03_18'],
3: ['Tuesday_2022_03_15', 'Wednesday_2022_03_16'],
5: ['Thursday_2022_03_17', 'Friday_2022_03_18'],
6: ['Friday_2022_03_18'],
7: ['Monday_2022_03_14'],
9: ['Wednesday_2022_03_16'],
10: ['Tuesday_2022_03_15'],
14: ['Wednesday_2022_03_16'],
16: ['Monday_2022_03_14', 'Tuesday_2022_03_15', 'Thursday_2022_03_17'],
17: ['Monday_2022_03_14', 'Wednesday_2022_03_16', 'Friday_2022_03_18'],
19: ['Monday_2022_03_14', 'Wednesday_2022_03_16', 'Thursday_2022_03_17'],
21: ['Tuesday_2022_03_15', 'Wednesday_2022_03_16'],
22: ['Tuesday_2022_03_15'],
23: ['Monday_2022_03_14', 'Thursday_2022_03_17'],
25: ['Monday_2022_03_14', 'Tuesday_2022_03_15'],
27: ['Wednesday_2022_03_16', 'Thursday_2022_03_17', 'Friday_2022_03_18'],
28: ['Tuesday_2022_03_15'],
29: ['Tuesday_2022_03_15', 'Thursday_2022_03_17', 'Friday_2022_03_18'],
30: ['Tuesday_2022_03_15', 'Thursday_2022_03_17'],
31: ['Tuesday_2022_03_15'],
32: ['Monday_2022_03_14'],
33: ['Tuesday_2022_03_15'],
40: ['Monday_2022_03_14', 'Wednesday_2022_03_16', 'Friday_2022_03_18'],
41: ['Tuesday_2022_03_15', 'Friday_2022_03_18'],
42: ['Thursday_2022_03_17', 'Friday_2022_03_18'],
43: ['Monday_2022_03_14', 'Tuesday_2022_03_15'],
44: ['Wednesday_2022_03_16', 'Thursday_2022_03_17', 'Friday_2022_03_18']}
轉載請註明出處，本文鏈接：https://www.uj5u.com/yidong/454569.html
上一篇：CodeIgniter4Routeurlnotfound“在此服務器上未找到請求的URL。”在Heroku上部署
下一篇：python中的字典鍵映射