Gradient

The gradient of a function $f(x,y,z)$ is the vector $\nabla f(x,y,z) = \begin{bmatrix} \dfrac{\partial f(x,y,z)}{\partial x} \\ \dfrac{\partial f(x,y,z)}{\partial y} \\ \dfrac{\partial f(x,y,z)}{\partial z} \\ \end{bmatrix}$