Primer on Gradients

Implementing explanation methods requires basic knowledge of gradients. So before diving deeper into the course, let’s first quickly review the concepts of gradients.

Gradients

Given a function $f(x)$, where $x = (x_1, x_2, ... x_d)$ is a $d$-dimensional vector, the gradient of $f(x)$ with respect to $x$, i.e., $\nabla_x f(x)$, is a $d$-dimensional vector given by