And, the way we can get it, so, it's called usually V, so, V here stands for velocity more than for vector. And, you just get it by taking the derivative of a position vector with respect to time.

根据它的原理，我们通常用v表示,这里的V更代表速率而不是矢量，你能通过,对一个关于时间的位置向量求导得到它。

youdao

So, speed, which is the scalar quantity is going to be just the magnitude of the vector, V.

因此，速度的大小即是,矢量V的模长。

youdao

v So -- So if the gradient vector is perpendicular to v OK, that's a good start.

所以梯度向量垂直于,很好，这是一个很好的开始。

youdao

So here's a program called Arg V, this is fancy speak for argument Vector, a list of arguments for the left or right.

这里有一个叫做ArgV的程序，这个设想讲述了,参数矢量，从左到右的一列参数。

哈佛公开课 - 计算机科学课程节选

The typical vector is called V or A or B something with an arrow on it.

表示矢量时一般在,字母 V,A 或者 B,上面加个箭头

耶鲁公开课 - 基础物理课程节选

If you want to write it as a vector equation, you want to write it as v square over r minus-- I want to say that it's pointing in the direction toward the center.

如果要写出矢量方程,就应该写成 -v^2 / r,也就是说,方向就向圆心

耶鲁公开课 - 基础物理课程节选