converting dictionary values to list in Python

Question

Suppose I have a dictionary (dict) with keys and values as below:

print(dict)

{'AAA': {'', '111', '222'}, 'BBB': {'222', '999', '555'}}

I want to extract the values from the dictionary in the form of a single string, i.e. type(values) = str, such as:

values = '111', '222', '999', 555'

but what I am getting is below under dict.values():

dict.keys()

dict_keys(['AAA', 'BBB'])

dict.values()

dict_values([{'', '111', '222'}, {'222', '999', '555'}])

How can I achieve the required result?

Anshul Goyal · Answer 1 · 2018-04-03T22:06:41.640

5

You can use itertools.chain to do this:

In [92]: from itertools import chain

In [93]: dct = {'AAA': {'', '111', '222'}, 'BBB': {'222', '999', '555'}}

In [94]: {x for x in chain(*dct.values()) if x}
Out[94]: {'111', '222', '555', '999'}

If you want to convert this output to a single string, just use an str() call on it, or use ", ".join(x for x in chain(*dct.values()) if x)

edited Apr 03 '18 at 22:06

answered Apr 03 '18 at 21:59

Anshul Goyal

73,278
37
149
186

That does not outputs a string...adding this will `', '.join(y for y in {x for x in chain(*d.values()) if x})` – drec4s Apr 03 '18 at 22:03
@drec4s I know it doesn't; Op says he wants `values = '111', '222', '999', 555'`, so the requirements aren't clear on that front. But I have made changes so that OP can call `str` on the set to get the values as a single string. – Anshul Goyal Apr 03 '18 at 22:04
1

OP clearly states he wants the output in "the form of a single string"... – drec4s Apr 03 '18 at 22:06
Nevertheless, this is the most efficient way to do it. +1 – drec4s Apr 03 '18 at 22:06

score 0 · Answer 2 · answered Apr 03 '18 at 21:59

I believe this is what you are after if you want them output as a single string:

mydict = {'AAA': {'', '111', '222'}, 'BBB': {'222', '999', '555'}}

out = []
for keys, values in mydict.items():
    [out.append(i) for i in values if i!='']

out = ','.join(set(out))

print(out)

print(type(out))

Outputs:

555,222,111,999

<class 'str'>

score 0 · Answer 3 · answered Apr 03 '18 at 22:00

0

Do you want something like

d = dict()
d[0] = '0'
str(d)

?

String manipulations are fairly straightforward after that

answered Apr 03 '18 at 22:00

kmartin · Answer 4 · 2018-04-03T22:11:01.937

0

Just use extend method:

values = []
for key in some_dict:
    values.extend(list(some_dict[key]))

If you need to delete the empty strings, use:

values = list(filter(None, values))

See this SE entry

Then you can convert it to a tuple if you wish :)

edited Apr 03 '18 at 22:11

answered Apr 03 '18 at 22:07

kmartin

194
3
9

This won't work, the values are a set not a list. While your approach is in the right direction, you can explore set.add method and correct the code – Anshul Goyal Apr 03 '18 at 22:08
Conversion added. – kmartin Apr 03 '18 at 22:11
1

not to be pedantic, but this won't output the correct result again. The value '222' will repeat twice, which it doesn't in the case of `set`s :) – Anshul Goyal Apr 03 '18 at 22:13

Sphinx · Answer 5 · 2018-04-03T22:28:38.247

This is another way to do without import any module.

dict = {'AAA': {'', '111', '222'}, 'BBB': {'222', '999', '555'}}
result = []
print([[result.append(item) or item for item in one_set if item] for one_set in dict.values()])
print(','.join(result)) #all non '' elements
print(','.join(set(result))) #all non '' and non duplicated elements

Output:

[['222', '111'], ['222', '999', '555']]
222,111,222,999,555
222,999,555,111
[Finished in 0.181s]

score 0 · Answer 6 · answered Apr 04 '18 at 06:14

0

You can try list comprehension in one line :

data={'AAA': {'', '111', '222'}, 'BBB': {'222', '999', '555'}}

print(set([k for i,j in data.items() for k in j if k]))

output:

{'222', '999', '111', '555'}

answered Apr 04 '18 at 06:14

Aaditya Ura

12,007
7
50
88

converting dictionary values to list in Python

6 Answers6

Linked