Python | Ways to remove numeric digits from given string

In Python, we can remove numeric digits from a string in multiple ways. For example, if we have a string like "Geeks123" and we want to remove the numbers to get "Geeks", we can use different methods to accomplish this. We can do this by using techniques such as list comprehension, regular expressions, string methods and filters.

Using Regular Expressions (re.sub())

Regular expressions (regex) in Python that allow us to search for patterns in text. In our case, we can use regex to find all the digits in the string and replace them with an empty string. The re.sub() function is used to search for a pattern in a string and replace it. In the pattern \d+, \d means "any digit" and + means "one or more". So \d+ matches all digits in the string.

import re

s = "geeks123"
result = re.sub(r'\d+', '', s)  # Remove all digits from the string
print(result)

geeks

Other methods that we can use to remove numeric digits from given string:

Using str.isalpha() with Loop

With this approach we iterate through each character in the string and check if it’s an alphabet letter. isalpha() method returns True if the character is a letter and False if it is not.

s = "geeks123"
result = ""

for char in s:
    if char.isalpha():  # Check if the character is not a number
        result += char   # Add it to result if it's a letter

print(result)

geeks

Using List Comprehension

List comprehension is a more concise way to achieve the same result as the loop. It combines the loop and the condition into a single line of code.

s = "geeks123"
result = ''.join([char for char in s if char.isalpha()])
print(result)

geeks

Explanation:

• The code uses a list comprehension to iterate over each character in the string s, adding only alphabetic characters (using char.isalpha()) to a new list, which is then joined into a single string using ''.join(). The result is "geeks".

Using filter() Function

filter() function is a built-in Python function that can be used to filter out certain elements from an iterable, like a string. In our case, we can filter out all characters that are not alphabetic. The filter() function takes two arguments: a function and an iterable. We use str.isalpha as the function, which checks whether a character is alphabetic. filter() will only keep the characters that pass the isalpha() check and remove the rest.

s = "geeks12332"
result = ''.join(filter(str.isalpha, s))  # Filter out non-letter characters
print(result)

geeks