Python merge multiple list inside one variable into one list

Question

I am having a hard time putting multiple list into one because they are all inside one variable.

here is an exemple:

What I have

a = ['1'], ['3'], ['3']

What I want

a = ['1', '3', '3']

How can I resolve that using Python 3.x

EDIT

here is the code I'm working on.

from itertools import chain

def compteur_voyelle(str):
    list_string = "aeoui"
    oldstr = str.lower()
    text = oldstr.replace(" ", "")
    print(text)

    for l in list_string:
        total = text.count(l).__str__()
        answer = list(chain(*total))
        print(answer)

compteur_voyelle("Saitama is the One Punch Man.")

Console Result :

saitamaistheonepunchman.
['4']
['2']
['1']
['1']
['2']

Akavall · Accepted Answer · 2017-01-19T18:13:18.950

9

You can use itertools.chain.

In [35]: from itertools import chain

In [36]: a = ['1'], ['3'], ['3']

In [37]: list(chain(*a))
Out[37]: ['1', '3', '3']

Or

In [39]: list(chain.from_iterable(a))
Out[39]: ['1', '3', '3']

edited Jan 19 '17 at 18:13

answered Dec 19 '15 at 23:38

Akavall

76,296
45
192
242

I just tried it, the lists are still separated I posted the code above, am I missing something? – Hiroyuki Nuri Dec 19 '15 at 23:48
1

answer = list(chain(*total)) print(answer) should be outside the for loop – Hari Dec 19 '15 at 23:51
@Hari I just get `['2']` instead of `['4', '2', '1', '1', '2']` if I put them outside. – Hiroyuki Nuri Dec 19 '15 at 23:54
1

@Sia Also `total` is a string, not a list of strings... . You probably can declare an empty list `answer = []` outside the loop, and just append to it on every iteration. – Akavall Dec 19 '15 at 23:55
@Akavall it worked for me, thanks. – Hiroyuki Nuri Dec 20 '15 at 00:05

score 2 · Answer 2 · answered Dec 20 '15 at 09:39

2

a = ['1'], ['3'], ['3']

>>> type(a)
<class 'tuple'>

a is tuple here. we can covert tuple into list.

>>> a = ['1'], ['3'], ['3']
>>> [value[0] for value in list(a)]
['1', '3', '3']

answered Dec 20 '15 at 09:39

bhawani shanker

79
3

score 0 · Answer 3 · answered Dec 20 '15 at 10:28

0

Following the same example as in other answers, i guess this can also be done using the sum built-in :

In [1]: a = [1], [3], [3]

In [2]: sum(a, [])
Out[2]: [1, 3, 3]

answered Dec 20 '15 at 10:28

mgc

4,750
1
22
36

Python merge multiple list inside one variable into one list

3 Answers3

Linked