remove [] from a dataframe in python

Question

I have a dataframe with []

I want to remove [] from the Name column

I tried this:

df['Name'] = df['Name'].str.replace("['", "")
df['Name'] = df['Name'].str.replace("']", "")

But it seems not working

What do you mean by it seems not working? Do you have an error? Does it give you an unexpected result? It will help us answer your problem — robinood, Dec 20 '22 at 10:50
unterminated character set at position 0 is the error message — , Dec 20 '22 at 10:52
@BrownBear AttributeError: Can only use .str accessor with string values! then i get this — , Dec 20 '22 at 10:53
put here example to create similar df to make the code reproducible https://stackoverflow.com/questions/20109391/how-to-make-good-reproducible-pandas-examples — Brown Bear, Dec 20 '22 at 10:54
Are you sure your column Name is a string? It can also be simply an array, where you can not use str.replace — robinood, Dec 20 '22 at 10:56
df['Name'] = df['name'].str.replace('[', '').str.replace(']', '') — Gedas Miksenas, Dec 20 '22 at 10:57

score 0 · Answer 1 · answered Dec 20 '22 at 10:58

You have an error in your code, namely the ' (single-quote) character. Tried the following:

import pandas as pd

df = pd.DataFrame.from_records(data=[
    {
        "Name": "[Name1]",
        "ID": 1
    },
    {
        "Name": "[Name2]",
        "ID": 2
    },
        {
        "Name": "[Name3]",
        "ID": 3
    }
])

print(df)
df['Name'] = df['Name'].str.replace("[", "")
df['Name'] = df['Name'].str.replace("]", "")
print(df)

which returned:

      Name  ID
0  [Name1]   1
1  [Name2]   2
2  [Name3]   3
/home/sawik/./playground.py:81: FutureWarning: The default value of regex will change from True to False in a future version. In addition, single character regular expressions will *not* be treated as literal strings when regex=True.
  df['Name'] = df['Name'].str.replace("[", "")
/home/sawik/./playground.py:82: FutureWarning: The default value of regex will change from True to False in a future version. In addition, single character regular expressions will *not* be treated as literal strings when regex=True.
  df['Name'] = df['Name'].str.replace("]", "")
    Name  ID
0  Name1   1
1  Name2   2
2  Name3   3

score 0 · Accepted Answer · answered Dec 20 '22 at 11:10

Your column consists of lists, not strings, so you can't use string operations on it. What you can (and should) do is to .join the lists of strings into strings separated by comma.

>>> df = pd.DataFrame({'Test': [['foo', 'bar'], ['baz']]})
>>> df
         Test
0  [foo, bar]
1       [baz]
>>> df.dtypes
Test    object
dtype: object
>>> df['Test'] = df.Test.str.join(',')
>>> df
      Test
0  foo,bar
1      baz

remove [] from a dataframe in python

2 Answers2