static meanAngle(arr) {
    let sin = 0.0;
    let cos = 0.0;

    for (var i = 0; i < arr.length; i++) {
      sin += Math.sin(arr[i]);
      cos += Math.cos(arr[i]);
    }

    return Math.atan2(sin / arr.length, cos / arr.length);
  }
Returns the means of the angles contained in an array. In radians.

@static
@param {Number[]} arr An array containing angles (in radians).
@returns {Number} The mean angle in radians.