declare class Vector { x: number; y: number; constructor(x?: number, y?: number); add(vector: Vector): Vector; subtract(vector: Vector): Vector; addScalar(scalar: number): Vector; divideScalar(scalar: number): Vector; multiplyScalar(scalar: number): Vector; getMagnitude(): number; getAngle(): number; clone(): Vector; toUnit(): Vector; static from(angle: number, magnitude: number): Vector; static sum(vectors: Vector[]): Vector; } export default Vector;