Python Convert String List to List

Question

So I have a list of python formatted like:

x = ['[1,2,3]', '[4,5,6,]', ...]

Is there a way to convert the "inner lists" to actual lists? So the output would be

x = [[1,2,3], [4,5,6], ....]

Thanks!

score 2 · Accepted Answer · answered Jun 13 '17 at 19:03

2

Another example with json:

>>> import json
>>> x = ['[1,2,3]', '[4,5,6]']
>>> [json.loads(y) for y in x]
[[1, 2, 3], [4, 5, 6]]

Please limit your strings to dicts and lists only.

answered Jun 13 '17 at 19:03

cs95

I accepted this answer versus the one proposed by khelwood (his solution did also solve my problem) because my full code already uses the json library. – Ahmed Jun 13 '17 at 19:23

score 1 · Answer 2 · answered Jun 13 '17 at 18:59

1

You can use ast.literal_eval for this kind of conversion. You can use map to apply the conversion to each element of your list.

from ast import literal_eval

x = ['[1,2,3]', '[4,5,6,]']
x = map(literal_eval, x)
print x

gives

[[1, 2, 3], [4, 5, 6]]

answered Jun 13 '17 at 18:59

khelwood

`ast.literal_eval` is great and it converts many types, but it'll give error if the list has any tags (i.e. `` etc) – Muhammad Mehran Khan Attari Jan 25 '20 at 05:30

score 1 · Answer 3 · answered Jun 13 '17 at 19:05

1

You can use eval to evaluate strings as code.

x = ['[1,2,3]', '[4,5,6,]']
y = [eval(s) for s in x]

answered Jun 13 '17 at 19:05

Josh Wight

3 Answers3