line element vector

例句：

1. 1.The line element vector is used to calculate the distance between two points on a plane.
   直线元素向量用于计算平面上两点之间的距离。
2. 2.In computer graphics, line element vectors are used to represent the shape of objects.
   在计算机图形学中，线元素向量用于表示物体的形状。
3. 3. The line element vector is also used in fluid dynamics to model the flow of fluids.
   线元素向量也在流体动力学中用于模拟流体的流动。