Python – Remove words containing list characters

Sometimes, in the process of data filtering we have a problem in which we need to remove words which are composite of certain letters. This kind of application is common in data science domain. Let’s discuss certain ways in which this task can be performed.

Method #1 : Using all() + list comprehension
The combination of above methods can be used to perform this task. In this, we just check for all list characters using all() in each list and filters out string which has any one of characters.

# Python3 code to demonstrate
# Remove words containing list characters
# using list comprehension + all()
from itertools import groupby

# initializing list
test_list = ['gfg', 'is', 'best', 'for', 'geeks']

# initializing char list
char_list = ['g', 'o']

# printing original list
print ("The original list is : " + str(test_list))

# printing character list
print ("The character list is : " + str(char_list))

# Remove words containing list characters
# using list comprehension + all()
res = [ele for ele in test_list if all(ch not in ele for ch in char_list)]

# printing result
print ("The filtered strings are : " + str(res))

Output :

The original list is : ['gfg', 'is', 'best', 'for', 'geeks']
The character list is : ['g', 'o']
The filtered strings are : ['is', 'best']

Method #2 : Using loop
This is brute method in which this task can be performed. In this we use loop and conditional statements to perform this task.

# Python3 code to demonstrate
# Remove words containing list characters
# using loop
from itertools import groupby

# initializing list
test_list = ['gfg', 'is', 'best', 'for', 'geeks']

# initializing char list
char_list = ['g', 'o']

# printing original list
print ("The original list is : " + str(test_list))

# printing character list
print ("The character list is : " + str(char_list))

# Remove words containing list characters
# using loop
res = []
flag = 1
for ele in test_list:
    for idx in char_list:
        if idx not in ele:
            flag = 1
        else:
            flag = 0
            break
    if(flag == 1):
        res.append(ele)

# printing result
print ("The filtered strings are : " + str(res))

Output :

The original list is : ['gfg', 'is', 'best', 'for', 'geeks']
The character list is : ['g', 'o']
The filtered strings are : ['is', 'best']