Pandas: Extract only non alphanumeric characters from the specified column of a given DataFrame

Last update on May 02 2025 12:51:40 (UTC/GMT +8 hours)

30. Extract Non-Alphanumeric Characters

Write a Pandas program to extract only non alphanumeric characters from the specified column of a given DataFrame.

Sample Solution:

Python Code :

import pandas as pd
import re as re
pd.set_option('display.max_columns', 10)
df = pd.DataFrame({
    'company_code': ['c0001#','c00@0^2','$c0003', 'c0003', '&c0004'],
    'year': ['year 1800','year 1700','year 2300', 'year 1900', 'year 2200']
    })
print("Original DataFrame:")
print(df)
def find_nonalpha(text):
    result = re.findall("[^A-Za-z0-9 ]",text)
    return result
df['nonalpha']=df['company_code'].apply(lambda x: find_nonalpha(x))
print("\Extracting only non alphanumeric characters from company_code:")
print(df)

Sample Output:

Original DataFrame:
  company_code       year
0       c0001#  year 1800
1      c00@0^2  year 1700
2       $c0003  year 2300
3        c0003  year 1900
4       &c0004  year 2200
\Extracting only non alphanumeric characters from company_code:
  company_code       year nonalpha
0       c0001#  year 1800      [#]
1      c00@0^2  year 1700   [@, ^]
2       $c0003  year 2300      [$]
3        c0003  year 1900       []
4       &c0004  year 2200      [&]

For more Practice: Solve these Related Problems:

Write a Pandas program to extract all non-alphanumeric characters from a DataFrame column using regex and then display the results.
Write a Pandas program to create a new column that contains only the non-alphanumeric characters extracted from a given text column.
Write a Pandas program to filter and output all special characters from a string column in a DataFrame using a regex pattern.
Write a Pandas program to remove alphanumeric characters from a column and then list the remaining punctuation and symbols.

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Next: Write a Pandas program to extract only punctuations from the specified column of a given DataFrame.

Python Code Editor:

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