EN
JavaScript - check words similarity (fuzzy compare with bigrams)
11 points
In this article, we would like to show how to check words similarity in JavaScript.
Below logic:
- calculates words bigrams,
- counts bigram hits to find similarity,
- divides hits by bigrams to calculate final words similarity.
Below checkSimilarity() function result indicates how two words are similar.
Similarity measured is from 0 where:
0- means: the worlds are totally different,>=1- means: the words are the same or contain similar part.
That kind of approach is may be applied in fuzzy search.
Practical example:
xxxxxxxxxx1
const createBigram = word => {2
const input = word.toLowerCase();3
const vector = [];4
for (let i = 0; i < input.length; ++i) {5
vector.push(input.slice(i, i + 2));6
}7
return vector;8
};9
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const checkSimilarity = (a, b) => {11
if (a.length > 0 && b.length > 0) {12
const aBigram = createBigram(a);13
const bBigram = createBigram(b);14
let hits = 0;15
for (let x = 0; x < aBigram.length; ++x) {16
for (let y = 0; y < bBigram.length; ++y) {17
if (aBigram[x] === bBigram[y]) {18
hits += 1;19
}20
}21
}22
if (hits > 0) {23
const union = aBigram.length + bBigram.length;24
return (2.0 * hits) / union;25
}26
}27
return 0;28
};29
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// Usage example:32
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console.log(checkSimilarity('Chris', 'Chris')); // 134
console.log(checkSimilarity('John1', 'John2')); // 0.635
console.log(checkSimilarity('Google', 'Gogle')); // 0.909090909090909136
console.log(checkSimilarity('Ann', 'Matt' )); // 0Note: do not compare sentences or whole texts using the above function - it may lead to comparison mistakes.
