Python - Remove suffix from string list

To remove a suffix from a list of strings, we identify and exclude elements that end with the specified suffix. This involves checking each string in the list and ensuring it doesn't have the unwanted suffix at the end, resulting in a list with only the desired elements.

Using list comprehension

Using List Comprehension, we can create a new list that excludes the elements with the unwanted suffix, avoiding the overhead of modifying the list in place.

li= ['allx', 'lovex', 'gfg', 'xit', 'is', 'bestx']
# Suffix to remove
s= 'x'
res = [word for word in li if not word.endswith(s)]
print(res)

['gfg', 'xit', 'is']

Explanation:

• for word in li: Thisloops through each element in the list li.
• if not word.endswith(suff):This checks whether each word does not end with the suffix s .

Using filter()

filter() function in Python can be used to filter out elements from a list based on a condition. In this case, it is combined with the endswith() method to exclude elements that end with a specified suffix.

li= ['allx', 'lovex', 'gfg', 'xit', 'is', 'bestx']
# Suffix to remove
s = 'x'
res = list(filter(lambda word: not word.endswith(s), li))
print(res)

['gfg', 'xit', 'is']

Explanation:

• filter(): This filters elements based on a condition.
• lambda word: not word.endswith(s): This checks if a word does not end with the suffix 'x'.
• not word.endswith(s): This excludes words that end with 'x'.
• list(): This converts the result into a list.

Using remove()

This method involves iterating through the list and removing elements in place. However, modifying the list while iterating over it can cause issues with skipped elements, so a copy of the list or iterating over a slice is often required.

li = ['allx', 'lovex', 'gfg', 'xit', 'is', 'bestx']
# Suffix
s = 'x'
for word in li[:]:
    if word.endswith(s):
        li.remove(word)
print(li)

['gfg', 'xit', 'is']

Explanation:

• for word in li[:] :This iterates over a copy of the list, ensuring changes don't affect the loop.
• if word.endswith(s): This checks if the word ends with the suffix 'x'.
• li.remove(word): This removes the word from the original list if it matches the condition, only removing the first occurrence.

Using pop()

This method iterates through the list and removes elements in place using pop(). Modifying the list while iterating can cause elements to shift, potentially leading to skipped checks. Proper index handling is required to ensure all elements are checked.

li = ['allx', 'lovex', 'gfg', 'xit', 'is', 'bestx']
# Suffix to remove
suff = 'x'
index = 0  # Start at the beginning of the list
while index < len(li):  # Loop through the list
    if li[index].endswith(suff): 
        li.pop(index) 
    else:
        index += 1 
        
print(li)

['gfg', 'xit', 'is']

Explanation:

• if li[index].endswith(suff): This checks if the current word ends with the suffix 'x'.
• li.pop(index): This removes the word at the current index if the condition is met.
• else: index += 1: This increments the index to check the next word if the condition is not met.