check if a string contains character except the ones in a given string python

Question

How can I check if a string (string1) contains characters except the ones in the following string (seq_letters):

string1 = 'SEQ'

seq_letters = 'ATCGRYMKSWHBVDN'

E and Q are not in seq_letters.

You can use a regex with negative group: re.fullmatch(r'[^%s]*' % seq_letters, string1) — Giacomo Alzetta
– Giacomo Alzetta, Commented Jul 16, 2019 at 8:10

Rakesh · Accepted Answer · 2019-07-16 08:09:15Z

6

Using set.difference

string1 = 'SEQ'
seq_letters = 'ATCGRYMKSWHBVDN'

print(set(string1).difference(seq_letters))

Output:

{'E', 'Q'}

answered Jul 16, 2019 at 8:08

Rakesh

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Comments

shubham · Accepted Answer · 2019-07-16 08:19:36Z

1

string1 = 'SEQ'
seq_letters = 'ATCGRYMKSWHBVDN'
result = []
for i in string1:
    if i not in seq_letters:
        result.append(i)
print(result)

answered Jul 16, 2019 at 8:19

shubham

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