Lagrange Interpolation in JavaScript

lagrangeInterpolation.js

function lagrangeInterpolation(xs, ys, x) {
    let y = 0;
    for(let i = 0; i < xs.length; i++) {
        let t = 1;
        for(let j = 0; j < xs.length; j++) {
            if(j !== i) {
                t *= (x - xs[j]) / (xs[i] - xs[j]);
            }
        }
        y += t * ys[i];
    }
    return y;
}