How to read an array list from csv file using python

Question

I have a csv file with ";" separator where information are look like,

Id;arrVal
0;[[84, 109, 423, 466]]
1;[[242, 192, 822, 594], [242, 640, 818, 911]]
2;[[123, 212, 401, 351]]

I am reading the csv file and want to get the array for specific Id by using following code

df = pd.read_csv("path/to/csv/file.csv", sep=";")
df[df['Id']==1].iloc[0]['arrVal']

It gives me the value [[242, 192, 822, 594], [242, 640, 818, 911]] but as a string. How can I extract as a 2D array?

Mark Tolonen · Accepted Answer · 2018-10-11 22:26:28Z

3

That column is also valid JSON syntax, so you could use:

import pandas as pd
import json

df = pd.read_csv('input.csv',sep=';')
L = json.loads(df[df['Id']==1].iloc[0]['arrVal'])

answered Oct 11, 2018 at 22:26

Mark Tolonen

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Comments

gherkin · Accepted Answer · 2018-10-11 21:41:57Z

2

x = ast.literal_eval(df[df['Id']==1].iloc[0]['arrVal'])

answered Oct 11, 2018 at 21:41

gherkin

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