Pandas: Count of occurrence of a specified substring in a DataFrame column

Last update on May 02 2025 12:51:47 (UTC/GMT +8 hours)

6. Count Substring Occurrence

Write a Pandas program to count of occurrence of a specified substring in a DataFrame column.

Sample Solution:

Python Code :

import pandas as pd
df = pd.DataFrame({
    'name_code': ['c001','c002','c022', 'c2002', 'c2222'],
    'date_of_birth ': ['12/05/2002','16/02/1999','25/09/1998','12/02/2022','15/09/1997'],
    'age': [18.5, 21.2, 22.5, 22, 23]
})
print("Original DataFrame:")
print(df)
print("\nCount occurrence of 2 in date_of_birth column:")
df['count'] = list(map(lambda x: x.count("2"), df['name_code']))
print(df)

Sample Output:

Original DataFrame:
  name_code date_of_birth    age
0      c001     12/05/2002  18.5
1      c002     16/02/1999  21.2
2      c022     25/09/1998  22.5
3     c2002     12/02/2022  22.0
4     c2222     15/09/1997  23.0

Count occurrence of 2 in date_of_birth column:
  name_code date_of_birth    age  count
0      c001     12/05/2002  18.5      0
1      c002     16/02/1999  21.2      1
2      c022     25/09/1998  22.5      2
3     c2002     12/02/2022  22.0      2
4     c2222     15/09/1997  23.0      4

For more Practice: Solve these Related Problems:

Write a Pandas program to count the occurrence of a given substring in a DataFrame column using vectorized string methods.
Write a Pandas program to compute the frequency of a specified substring in multiple columns and then aggregate the counts.
Write a Pandas program to count substring occurrences in a column and then filter rows where the count exceeds a threshold.
Write a Pandas program to generate a new column with the count of a specific substring found in each row of a DataFrame column.

Go to:

Previous: Write a Pandas program to capitalize all the string values of specified columns of a given DataFrame.
Next: Write a Pandas program to find the index of a given substring of a DataFrame column.

Python Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.