function equals$2(a, b) {
    return Math.abs(dot$3(a, b)) >= 1 - EPSILON;
  }
Returns whether or not the quaternions point approximately to the same direction.

Both quaternions are assumed to be unit length.

@param {ReadonlyQuat} a The first unit quaternion.
@param {ReadonlyQuat} b The second unit quaternion.
@returns {Boolean} True if the quaternions are equal, false otherwise.