Convert a list of strings containing list-of-integers into an array

Question

I have a series that is a list of lists that contain integers that I am attempting to turn into an array. This is a small snip-it of the list I am trying to convert into an array.

['[0, 0, 0, 0, 0, 0, 0, 0, 0, 1]',

'[0, 0, 0, 0, 0, 0, 0, 0, 1, 0]',

'[0, 0, 0, 0, 0, 0, 0, 1, 0, 0]',

'[0, 0, 0, 0, 0, 0, 0, 1, 0, 1]',

'[0, 0, 0, 0, 0, 0, 0, 1, 1, 1]']

I've tried to replace the quotes with .replace, but that hasn't worked out.

sequence = [i.replace(" '' ", ' ') for i in sequence]

So you have a list of strings which each represent a list of integers? — quamrana, Feb 16 '20 at 18:33
Yes! And I want to convert that list of integers into an array. — febreeze, Feb 16 '20 at 18:33
You may use `ast.literal_eval()` to turn your strings into Python lists... — Sergey Bushmanov, Feb 16 '20 at 18:37
Does this answer your question? [Convert string representation of list to list](https://stackoverflow.com/questions/1894269/convert-string-representation-of-list-to-list) — AMC, Feb 16 '20 at 19:25

Guy · Accepted Answer · 2020-02-16T19:04:22.397

You can use ast.literal_eval to change the string to list of lists of ints

sequence = [literal_eval(i) for i in sequence]

# [[0, 0, 0, 0, 0, 0, 0, 0, 0, 1], [0, 0, 0, 0, 0, 0, 0, 0, 1, 0], [0, 0, 0, 0, 0, 0, 0, 1, 0, 0], [0, 0, 0, 0, 0, 0, 0, 1, 0, 1], [0, 0, 0, 0, 0, 0, 0, 1, 1, 1]]

You can change it to numpy array

import numpy as np

array = np.asarray(sequence)
print(array)

output

[[0 0 0 0 0 0 0 0 0 1]
 [0 0 0 0 0 0 0 0 1 0]
 [0 0 0 0 0 0 0 1 0 0]
 [0 0 0 0 0 0 0 1 0 1]
 [0 0 0 0 0 0 0 1 1 1]]

Or to 1d pandas array

import pandas as pd

array = pd.array([item for items in sequence for item in items])
print(array)

outout

<IntegerArray>
[0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0,
 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1]
Length: 50, dtype: Int64

Convert a list of strings containing list-of-integers into an array

1 Answers1