@langchain/core/dist/utils/ml-distance/similarities.js

Core LangChain.js abstractions and schemas

/**
 * Returns the average of cosine distances between vectors a and b
 * @param a - first vector
 * @param b - second vector
 *
 */
export function cosine(a, b) {
    let p = 0;
    let p2 = 0;
    let q2 = 0;
    for (let i = 0; i < a.length; i++) {
        p += a[i] * b[i];
        p2 += a[i] * a[i];
        q2 += b[i] * b[i];
    }
    return p / (Math.sqrt(p2) * Math.sqrt(q2));
}