c#-计算两个空间点形成的单位向量

介绍一种计算两个空间点单位向量的方法，代码如下：

   /// <summary>        /// 计算单位向量        /// </summary>        /// <param name="fromPoint">起点</param>        /// <param name="toPoint">终点</param>        /// <returns></returns>        private double[] GetUnitVec(double[] fromPoint, double[] toPoint)        {            double dist = Math.Sqrt((fromPoint[0] - toPoint[0]) * (fromPoint[0] - toPoint[0]) +                (fromPoint[1] - toPoint[1]) * (fromPoint[1] - toPoint[1]) +                (fromPoint[2] - toPoint[2]) * (fromPoint[2] - toPoint[2]));            return new double[] { (toPoint[0] - fromPoint[0]) / dist, (toPoint[1] - fromPoint[1]) / dist, (toPoint[2] - fromPoint[2]) / dist };        }