Figure 19.
The grid uses xi on the vertical axis and eta on the horizontal axis. The vertical increment is labelled delta xi, and the horizontal increment is labelled delta eta. The indexed points are i minus 1, j plus 1, i, j plus 1, i plus 1, j plus 1, i minus 1, j, i, j, i plus 1, j, i minus 1, j minus 1, i, j minus 1, and i plus 1, j minus 1.Grid discretization