The steps of the example scan (i.e. rows in Figure ) are described in the following example. For clarity of presentation, it is necessary to define the basic procedures within a step and the separation between steps. At the start of a step, constrained optimization calculations are started based on the results of the previous step. Upon completion of these calculations, some grid points are set as "active points" as described below, then the step is concluded. The result of one step is independent of the order of completion of the individual optimizations within a step.