text: const Point = function(x_point=0, y_point=0) {
    const x = x_point
    const y = y_point
  
    return {
      get x() {
        return x
      },
      get y() {
        return y
      },
      /* get polar radius */
      get r() {
        return Math.sqrt(x*x + y*y)
      },
      /* returns the angle theta of an (x, y) point */
      theta() {
          return Math.atan2(y, x)
      },
      /* angle between two points */
      angleTo(to) {
          dx = to.x - x
          dy = to.y - y
          return Math.atan2(dy, dx)
      }
    }
  }
  module.exports = Point
  