gradient orientation

• 梯度方向

gradient orientation的用法和样例：

例句

1. In the forward step, the eikonal equation was solved by finite-difference method.Raypaths were determined in the minus gradient direction of travel time.
   正演采用快速的有限差分求解程函方程的方法求取旅行时，利用旅行时的负梯度方向求取射线路径。