Introduction to Python | Pandas Series .str.findall()

In Python, the Pandas library provides powerful tools for data analysis and manipulation. One of the useful methods offered by the Pandas Series object is .str.findall(). This method allows us to extract all occurrences of a pattern from each string element in a Series.

Syntax

The syntax for using the .str.findall() method is as follows:

Series.str.findall(pat, flags=0)

Parameters:

• pat: The pattern to be searched in each string element of the Series. It can be a string or a regular expression.
• flags: An optional parameter that can be used to modify the behavior of the search. It supports regular expression flags such as re.IGNORECASE, re.MULTILINE, etc.

Returns:

• A Series containing lists of all occurrences of the pattern in each string element. If there are no matches, an empty list is returned.

Example

Consider the following example to understand how to use the .str.findall() method:

import pandas as pd

# Create a Series with string elements
s = pd.Series(['apple', 'banana', 'orange', 'grape'])

# Use str.findall() to find all occurrences of 'a' in each string element
result = s.str.findall('a')

print(result)

Output:

0    [a]
1     []
2     [a]
3      []
dtype: object

In the example above, we first import the Pandas library and create a Series s with several fruit names. We then apply the .str.findall() method on the Series to find all occurrences of the letter 'a' in each string. The method returns a new Series where each element is a list containing the occurrences of 'a' in the corresponding string. If there are no matches, an empty list is returned.

Conclusion

The .str.findall() method in the Pandas library provides a convenient way to extract all occurrences of a pattern from string elements in a Series. It can be useful for various data analysis and manipulation tasks. Remember to always refer to the documentation for more details and examples on working with this method.