\subsection{ Pseudo Code for SOR---Successive Over Relaxation} \begin{tabbing} \hspace{2em} Choose an initial guess $x^{(0)}$ to the solution $x$. \\ \hspace{2em} {\bf for} \= $k = 1$,2,$\ldots$ \\ \hspace{2em} \> {\bf for} \= $i = 1$,2,$\ldots$,$n$ \\ \hspace{2em} \> \> $\sigma = 0$ \\ \hspace{2em} \> \> {\bf for} \= $j=1$,2,$\ldots$,$i-1$ \\ \hspace{2em} \> \> \> $\sigma = \sigma + a_{i,j}\, x_j^{(k)}$ \\ \hspace{2em} \> \> {\bf end} \\ \hspace{2em} \> \> {\bf for} $j=i+1$,$\ldots$,$n$ \\ \hspace{2em} \> \> \> $\sigma = \sigma + a_{i,j}\, x_j^{(k-1)}$ \\ \hspace{2em} \> \> {\bf end} \\ \hspace{2em} \> \> $\sigma = \left( b_i - \sigma \right)/a_{i,i}$ \\ \hspace{2em} \> \> $x_i^{(k)} = x_i^{(k-1)} + \omega\left( \sigma - x_i^{(k-1)}\right)$ \\ \hspace{2em} \> {\bf end} \\ \hspace{2em} \> check convergence; continue if necessary \\ \hspace{2em} {\bf end} \\ \end{tabbing} \begin{center} The SOR Method \end{center}