Let's say that I have the following matrix: $\begin{bmatrix} 5 &3 &0 \\ 0 &0 &5 \\ 7 &3 &1 \end{bmatrix}$
How do I symmetrize this matrix, so that I get the following? I am confused about where the original matrix components get moved around to.
$\left (\begin{bmatrix} 5 &3 &0 \\ 0 &0 &5 \\ 7 &3 &1 \end{bmatrix}+\begin{bmatrix} 5 &0 &7 \\ 3 &0 &3 \\ 0 &5 &1 \end{bmatrix} \right ) = \begin{bmatrix} 10 &3 &7 \\ 3 &0 &8 \\ 7 &8 &2 \end{bmatrix}$