问题描述
如何将此问题归纳为可能是元组的案例关键字?
How to generalize this question to the case keys that may be tuples?
即使在所有字符串键的情况下,这也是一个好处,如果将它们累积到一个元组,则不需要临时分隔符(尽管JSON导出是另一回事):
As a benefit even in the case of all string keys, if these are accumulated to a tuple, there's no need for ad-hoc separators (though JSON export is another matter):
一种方法是基于此答案.我尝试了2个版本:
one approach is to base it on this answer. I tried 2 versions:
def flatten_keys(d,handler,prefix=[]):
return {handler(prefix,k) if prefix else k : v
for kk, vv in d.items()
for k, v in flatten_keys(vv, handler, kk).items()
} if isinstance(d, dict) else { prefix : d }
元组处理程序在哪里:
def tuple_handler_1(prefix,k):
return tuple([prefix]+[k])
def tuple_handler_2(prefix,k):
return tuple(flatten_container((prefix,k)))
使用实用程序生成器:
def flatten_container(container):
for i in container:
if isinstance(i, (list,tuple)):
for j in flatten_container(i):
yield j
else:
yield i
考虑其中一个测试字典,但使用元组键('hgf',1)
:
Consider one of the test dict's but using a tuple key ('hgf',1)
:
data = {'abc':123, ('hgf',1):{'gh':432, 'yu':433}, 'gfd':902, 'xzxzxz':{"432":{'0b0b0b':231}, "43234":1321}}
均未达到预期的效果:
flatten_keys(data,tuple_handler_1)
('xzxzxz',('432','0b0b0b'))
.没有展平
第二个将输入的元组键变平
And the 2nd flattens the input tuple key
flatten_keys(data,tuple_handler_2)
扁平化方法是否有明显的修改,可以正确连接字符串和其他哈希值?
Is there an obvious modification of the flatten method that will correctly join strings and other hashables?
编辑
根据下面的评论,使用此方法处理键冲突是字符串键的基本情况,例如 {'a_b':{'c':1},'a':{'b_c':2}}
.
As per comments below, a problem handling key-clash with this method is inherent the base case of strings keys, eg {'a_b':{'c':1}, 'a':{'b_c':2}}
.
因此,即使对于 len
1个键路径,每个键路径也应该是一个元组,以避免键冲突,例如 {(((1,2),):3,(1,2):4}}
.
Thus each key path should be a be tuple even in for len
1 key paths to avoid key clash eg {((1,2),): 3, (1,2):4}}
.
推荐答案
假设您需要以下输入/输出
Assuming you want the following input/output
# input
{'abc': 123,
('hgf', 1): {'gh': 432, 'yu': 433},
'gfd': 902,
'xzxzxz': {'432': {'0b0b0b': 231}, '43234': 1321}}
# output
{('abc',): 123,
(('hgf', 1), 'gh'): 432,
(('hgf', 1), 'yu'): 433,
('gfd',): 902,
('xzxzxz', '432', '0b0b0b'): 231,
('xzxzxz', '43234'): 1321}
一种方法是对字典进行递归,直到找到一个非字典值,然后在递归过程中将当前键作为元组向下传递.
One approach is to recurse on your dictionary until you find a non-dictionary value and pass down the current key as a tuple during the recursion.
def flatten_dict(deep_dict):
def do_flatten(deep_dict, current_key):
for key, value in deep_dict.items():
# the key will be a flattened tuple
# but the type of `key` is not touched
new_key = current_key + (key,)
# if we have a dict, we recurse
if isinstance(value, dict):
yield from do_flatten(value, new_key)
else:
yield (new_key, value)
return dict(do_flatten(deep_dict, ()))
这篇关于用元组键展平嵌套字典的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!