Comparing 2 variables characters (Python)

Question

I want to compare 2 string variables and return the number of characters that are shared between the 2 strings. So "work" and "what" would return "1/4" since 1 out of 4 letters (only w in this example) are the same between the 2 strings.

Answer 1

This gives you the number of letters that appear in both words in the same position:

sum(1 for a, b in zip(word1, word2) if a == b)

zip gives you an iterator for each character in both words at the same time, and you simply sum 1 for each time they match.

This gives you the generally shared letters between both words in any position:

len(set(word1) & set(word2))

This creates two sets of letters, takes the intersection of both sets, and tells you how big that intersection is.

Answer 2

Are you asking for something like this?

a = "hello"
print(list(a))

b = "hell"

counter=0
for x in list(a):
    if x in list(b):
    counter+=1

print(str(counter)+"/"+str(len(list(b))))

This is taking the string stored in variable a, looping through the characters and comparing to the string stored in variable b. Finally; it prints the number of characters in a that were also in b over the length of the string stored in b.

Answer 3

You might what to consider using difflib as it seems to cover your usecase but also extends it to strings of different lengths.

Example 1

import difflib

sequence_matcher = difflib.SequenceMatcher(a='work', b='what')

sequence_matcher.ratio() # 0.25

Example 2

import difflib

sequence_matcher = difflib.SequenceMatcher(a='work', b='works')

sequence_matcher.ratio() # 0.889