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Python-拼合字典列表

更新时间:2023-01-16 21:25:20

您可以使用

You can do the following, using itertools.chain:

>>> from itertools import chain
# timeit: ~3.40
>>> [dict(chain(*map(dict.items, d.values()))) for d in data]
[{'l': 'Apple', 
  'b': 'Milk', 
  'd': 'Meatball', 
  'favourite': 'coke', 
  'dislike': 'juice'}, 
 {'l': 'Apple1', 
  'b': 'Milk1', 
  'dislike': 'juice3', 
  'favourite': 'coke2', 
  'd': 'Meatball2'}]

chainmap*的用法使该表达式成为以下双重嵌套理解的简写,它实际上在我的系统上表现更好(Python 3.5.2),并且不再那么长:

The usage of chain, map, * make this expression a shorthand for the following doubly nested comprehension which actually performs better on my system (Python 3.5.2) and isn't that much longer:

# timeit: ~2.04
[{k: v for x in d.values() for k, v in x.items()} for d in data]
# Or, not using items, but lookup by key
# timeit: ~1.67
[{k: x[k] for x in d.values() for k in x} for d in data]

注意:

RoadRunner的循环和更新方法在timeit: ~1.37

Note:

RoadRunner's loop-and-update approach outperforms both these one-liners at timeit: ~1.37