Question

有关具有唯一值的元组列表，例如：

a = [(1, 2), (3, 4), (5, 6)]

我想创建一张地图：

b = {}
for t in a:
    for tt in t:
        b[tt] = t

>>> {1: (1, 2), 2: (1, 2), 3: (3, 4), 4: (3, 4), 5: (5, 6), 6: (5, 6)}

如果没有明确的for循环，是否有更好/更方便的方法来实现这一目标？一种方法可能是使用dict.update，尽管这可能会让元组中的许多项目变得丑陋：

[(b.update({t1: (t1, t2)}), b.update({t2: (t1, t2)})) for t1, t2 in a]

Answer 1

使用词典理解：

>>> a = [(1, 2), (3, 4), (5, 6)]
>>> {i: tup for tup in a for i in tup}
{1: (1, 2), 2: (1, 2), 3: (3, 4), 4: (3, 4), 5: (5, 6), 6: (5, 6)}

Answer 2

from itertools import chain
flatten = chain.from_iterable

a = [(1, 2), (3, 4), (5, 6)]
d = dict(flatten(((k, (k, v)), (v, (k, v))) for k, v in a))

print(d)

Answer 3

字典理解：

{**{k: (k, v) for k, v in a}, **{v: (k, v) for k, v in a}}

方便的方法为元组列表创建地图

3 个答案: