python data array string convert to list

Question

Now I have a string like this：

data = "[[1,'00007',0.19],[2,'00008',0.29],[3,'00009',0.49],[4,'00010',0.59]]"

print(type(data))

<class 'str'>

in python this is like data array out,but it is a string, now I want convert this string to the real data array <class 'list'> , How should I do this

Take a look at https://stackoverflow.com/questions/743806/split-string-into-a-list-in-python for inspiration. — Mike P, Nov 27 '15 at 09:00
how do you get `data` ? maybe you shouldn't convert array to string ? — furas, Nov 27 '15 at 09:01

score 2 · Accepted Answer · answered Nov 27 '15 at 08:58

2

You could do

eval(data)

to parse its content.

answered Nov 27 '15 at 08:58

elzell

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use of `eval` is considered bad – The6thSense Nov 27 '15 at 09:24
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It's unsafe, there you're right. Simply depends on the application - if used in a little script without user interaction it should not be a problem, I'd say. – elzell Nov 27 '15 at 09:37
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Just wanted to add it there since the OP should know when to use it :) – The6thSense Nov 27 '15 at 09:40

score 2 · Answer 2 · edited Jun 20 '20 at 09:12

Use ast.literal_eval: as the documentation says-

Safely evaluate an expression node or a Unicode or Latin-1 encoded string containing a Python literal or container display.

The string or node provided may only consist of the following Python literal structures: strings, numbers, tuples, lists, dicts, booleans, and None.

>>> import ast

>>> data = "[[1,'00007',0.19],[2,'00008',0.29],[3,'00009',0.49],[4,'00010',0.59]]"
>>> ast.literal_eval(data)
[[1, '00007', 0.19], [2, '00008', 0.29], [3, '00009', 0.49], [4, '00010', 0.59]]

>>> print(type(ast.literal_eval(data)))
>>> <type 'list'>

Avoid using eval unless truly needed. Details at.

score 0 · Answer 3 · answered Nov 27 '15 at 09:24

0

Following on from your definition of data:

data_list = data.replace("[","").replace("]","").replace("'","").split(",")
new_list = [data_list[x:x+3] for x in range(0, len(data_list), 3)]

Though everything in the result is now a string.

answered Nov 27 '15 at 09:24

Chris Geatch

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python data array string convert to list

3 Answers3