1、The directional derivative according to the vector fields was introduced.
引入了相應于矢量場的方向導數。

2、The directional derivative in a direction that's perpendicular to the gradient is basically zero.
垂直于梯度的方向上,方向導數為零。

3、We discuss several different definitions of directional derivative and gradient vector.
討論了幾種不同的方向導數和梯度的定義。

4、Well, it's actually the directional derivative in that direction.
它其實是那個方向的方向導數。

directional derivative翻譯