PA=\left[
\begin{array}{ccc}
0 & 1 & 0 \\
1 & 0 & 0 \\
0 & 0 & 1
\end{array}
\right]\left[
\begin{array}{ccc}
1 & 2 & 3 \\
4 & 5 & 6 \\
7 & 8 & 9
\end{array}
\right] =
\left[
\begin{array}{ccc}
4 & 5 & 6 \\
1 & 2 & 3 \\
7 & 8 & 9
\end{array}
\right]