On the left is a plot of the log of the maximum residual vs iteration count. There are three curves, one for each zone. For each zone, the log of the maximum residual decreases from about -0.5 to -3.5 as the iteration count increases from 0 to about 1000, then oscillates about that level for the remainder of the iterations.

On the right is a plot of the log of the L₂ norm of the residual vs iteration count, again with a separate curve for each zone. For each zone, the log of the L₂ norm decreases from about -1.5 to -4.0 as the iteration count increases from 0 to about 1000, then oscillates about that level for the remainder of the iterations.