I am attempting to work on a permutation matrix problem. I just don't understand where the Unit Basis Vector comes in for this particular problem:
Let p = $$ \begin{pmatrix} 2\\ 0\\ 1\\ \end{pmatrix} $$ Compute P(p) $$\begin{pmatrix} -2 & 1 & 2\\ 3 & 2 & 1\\ -1 & 0 & -3\\ \end{pmatrix} $$
Could someone kindly demonstrate how problems like these are typically solved. (I did try watching YouTube, but P(p) (lowercase) is always a Unit basis vector/matrix.