If entropy is
$$H(X)=\sum_{i=1}^{N} p(x_i) \ln\bigg(\frac{1}{p(x_i)}\bigg)$$
how can this be written in matrix notation found in linear algebra, which replaces product summations with bold-faced vectors, i.e. $\mathbf{p}$?
Also not sure how the natural log of a vector (here, vector of inverse probabilities) can be written as a bold vector. would that part just be $\ln(\mathbf{p}^{-1})$?