A minimalist (amateur) implementation of 'Vector', along with cosineSimilarity

Vector.js

class Vector {
    constructor(VectorArray) {
        //TODO: Check things?
        this._values = VectorArray;
    }
    toArray() {
        return this._values;
    }
    get length() {
        return this._values.length;
    }
    get magnitude() {
        let squareSum = 0;
        for(let i of this._values) {
            squareSum+=i**2;
        }
        return squareSum**0.5
    }
    static dotProduct(a, b) {
        if(a.length!=b.length) throw Error("Bad vector");
        let sum = 0;
        for(let i = 0; i<a.length; i++) {
            sum+=(a._values[i]*b._values[i]);
        }
        return sum;
    }
    static cosineSimilarity(a, b) {
        return Vector.dotProduct(a, b)/(a.magnitude * b.magnitude);
    }
}