Cosine Similarity

cosineSimilarity.ts

function cosineSimilarity(a: number[], b: number[]) {
  let dotProduct = 0;
  let magnitudeA = 0;
  let magnitudeB = 0;
  for (let i = 0; i < a.length; i++) {
    dotProduct += (a[i] * b[i]);
    magnitudeA += (a[i] * a[i]);
    magnitudeB += (b[i] * b[i]);
  }
  magnitudeA = Math.sqrt(magnitudeA);
  magnitudeB = Math.sqrt(magnitudeB);
  const similarity = (dotProduct) / ((magnitudeA) * (magnitudeB));
  return similarity;
}


const array1 = [1, 0, 0, 1];
const array2 = [1, 0, 0, 0];

const p = cosineSimilarity(array1, array2);
console.log(p);