Question

I have two dictionaries:

{
'1234':
    {
        '2015-05-31T00:00:00.000Z': 795,
        '2015-05-21T00:00:00.000Z': 985,
        '2015-05-29T00:00:00.000Z': 805,
        '2015-05-28T00:00:00.000Z': 955,
        '2015-06-04T00:00:00.000Z': 1365,
        '2015-05-24T00:00:00.000Z': 845,
        '2015-06-03T00:00:00.000Z': 1545,
        '2015-05-23T00:00:00.000Z': 825,
        '2015-05-30T00:00:00.000Z': 875,
        '2015-05-22T00:00:00.000Z': 1165,
        '2015-05-27T00:00:00.000Z': 1065,
        '2015-06-01T00:00:00.000Z': 1145,
        '2015-06-05T00:00:00.000Z': 625,
        '2015-05-20T00:00:00.000Z': 745,
        '2015-06-02T00:00:00.000Z': 1405,
        '2015-05-26T00:00:00.000Z': 1255,
        '2015-05-25T00:00:00.000Z': 1135
    }
}

and

{
'1234':
    {
        '2015-05-31T00:00:00.000Z': 794,
        '2015-05-21T00:00:00.000Z': 980,
        '2015-05-29T00:00:00.000Z': 802,
        '2015-06-02T00:00:00.000Z': 1400,
        '2015-05-26T00:00:00.000Z': 1256,
        '2015-05-25T00:00:00.000Z': 1138
    }
}

How can I merge these two dicts with following and if a key-value item is existing, merge the two value?

Answer 1

您可以使用update

将dict_b添加到dict_a中

dict_a.update(dict_b)

这将用dict_b中的值覆盖dict_a中的值，其中有重叠的键，并且它还会添加来自dict_b的任何新键。

如果你想把它放在第三个字典中，不影响前两个字典，那么先复制字典

dict_c = dict_a.copy()
dict_c.update(dict_b)

Answer 2

如果要合并它们，可以遍历dict。不确定这是否是你最好的方式。

dict1 = {'1234': {'2015-05-31T00:00:00.000Z': 795, '2015-05-21T00:00:00.000Z': 985, '2015-05-29T00:00:00.000Z': 805, '2015-05-28T00:00:00.000Z': 955, '2015-06-04T00:00:00.000Z': 1365, '2015-05-24T00:00:00.000Z': 845, '2015-06-03T00:00:00.000Z': 1545, '2015-05-23T00:00:00.000Z': 825, '2015-05-30T00:00:00.000Z': 875, '2015-05-22T00:00:00.000Z': 1165, '2015-05-27T00:00:00.000Z': 1065, '2015-06-01T00:00:00.000Z': 1145, '2015-06-05T00:00:00.000Z': 625, '2015-05-20T00:00:00.000Z': 745, '2015-06-02T00:00:00.000Z': 1405, '2015-05-26T00:00:00.000Z': 1255, '2015-05-25T00:00:00.000Z': 1135}}
dict2 = {'1234': {'2015-05-31T00:00:00.000Z': 794, '2015-05-21T00:00:00.000Z': 980, '2015-05-29T00:00:00.000Z': 802, '2015-06-02T00:00:00.000Z': 1400, '2015-05-26T00:00:00.000Z': 1256, '2015-05-25T00:00:00.000Z': 1138}}
dict3 = {'1234': {}}

for key, value in dict1['1234'].iteritems():
    if key in dict2['1234'].keys():
        dict3['1234'][key] = value + dict2['1234'][key]
    else:
        dict3['1234'][key] = value

输出：

{
    '1234': 
        {
        '2015-05-31T00:00:00.000Z': 1589,
        '2015-05-26T00:00:00.000Z': 2511,
        '2015-05-21T00:00:00.000Z': 1965,
        '2015-05-22T00:00:00.000Z': 1165,
        '2015-05-27T00:00:00.000Z': 1065,
        '2015-06-01T00:00:00.000Z': 1145,
        '2015-05-28T00:00:00.000Z': 955,
        '2015-06-05T00:00:00.000Z': 625,
        '2015-06-02T00:00:00.000Z': 2805,
        '2015-06-04T00:00:00.000Z': 1365,
        '2015-05-20T00:00:00.000Z': 745,
        '2015-05-23T00:00:00.000Z': 825,
        '2015-05-24T00:00:00.000Z': 845,
        '2015-05-30T00:00:00.000Z': 875,
        '2015-05-25T00:00:00.000Z': 2273,
        '2015-06-03T00:00:00.000Z': 1545,
        '2015-05-29T00:00:00.000Z': 1607
        }
}

显然已经有了一个模块。根据{{3}};

Answer 3

这可能是另一种解决方案：

from itertools import chain
z = dict(chain(dict_a.iteritems(), dict_b.iteritems()))

与copy解决方案相比，这在性能方面得分更高。

Answer 4

我不确定你的意思是“合并”。如果合并它们，相同的键的值将被覆盖。我个人会将字典转换为字符串，然后进行一些更改并使用literal_eval将所有内容转换回字典。它运作得很好。

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import ast

d1 ={'1234':{'2015-05-31T00:00:00.000Z':795}}
d2 ={'1234':{'2015-05-31T00:00:00.000Z':794}}

s=str(d1)+str(d2)
s=s.replace('}{', ',')

d3=ast.literal_eval(s)

print d3

输出：

{'1234': {'2015-05-31T00:00:00.000Z': 794}}

如果这就是你的意思。

Answer 5

如果您希望将密钥匹配的值添加到一起：

new_dict = {}

for key in dict_2.keys():
    new_dict[key] = {}
    for subkey in dict_2[key]:
        if subkey in dict_1[key]:
            result = dict_1[key][subkey] + dict_2[key][subkey]
            new_dict[key][subkey] = result

print(new_dict)

输出：

{
    '1234': 
        {
            '2015-05-31T00:00:00.000Z': 1589, 
            '2015-05-26T00:00:00.000Z': 2511, 
            '2015-05-21T00:00:00.000Z': 1965, 
            '2015-06-02T00:00:00.000Z': 2805, 
            '2015-05-25T00:00:00.000Z': 2273, 
            '2015-05-29T00:00:00.000Z': 1607
         }
}

How can I merge two dictionaries with values?

5 个答案: