# Sector Specs

Sector Specs... takes you to the Sector Specs dialog. When the sector tool has been used to define model sectors, the Sector Specs dialog will enable you to specify the model sectors which will be run in a simulation. The software shows a maximum of 120 sectors in a given model, when the main monitor of your computer is 13 inches or larger. For smaller monitors, the software shows a maximum of 65 sectors. The Sector Specs dialog is illustrated in Figure 3-22.

Figure 3-22 Sector Specs Dialog

As the Figure shows, the dialog contains two radio buttons. The default is to run the entire model. When Run Selected Sectors is activated, all model sectors which have been fully defined are available to be run. A fully defined sector will have all variables within it defined, all flows in and out of the sector defined, and all variables on originating ends of connectors coming into the sector defined. Simply check those sectors which you want to run.

Clear All unchecks all selected model sectors. Cancel exits the dialog without registering any changes. OK registers the changes you make, and then exits the dialog.

Whenever you run a model using the Run Selected Sectors option, the software will apply the following rules to isolate the selected sectors from the rest of the model:

1. Building blocks which are entirely within a running sector will be run dynamically in the sector's simulation.

2. Flows between running sectors will be run dynamically.

3. Stocks, flows and converters which are not part of a running sector will be held constant at their initial values. Stocks and converters will report this initial value in Tables and in Numeric Displays.

4. If the flow regulator is within a running sector, an outflow from a running sector (either to the model diagram or to a non-running sector) will be treated as flowing into a cloud.

5. If the flow regulator is outside of a running sector, an outflow from a running sector (either to the model diagram or to a non-running sector) will be held constant at its initial value unless it is defined by a variable within an active sector, in which case it could be dynamic. Flows from Queues will be set to zero.

6. If the flow regulator is within a running sector, an inflow to a running sector (either from the model diagram or from a non-running sector) will be run according to its explicit flow logic unless it is dependent on variables outside the running sector(s), in which case the flow will be held constant at its initial value.

7. If the flow regulator is outside of a running sector, an inflow to a running sector (either from the model diagram or from a non-running sector) will be held constant at its initial value, subject to any active (i.e., dynamically changing) logic coming from the running sector(s).

Helpful Hint: If you have selected a set of model sectors to be run in a sector-by-sector analysis, depressing the alt key (Windows) or the option key (Macintosh) as you choose the Run menu will change the display of the Sector Specs... item to Disable Sector Run or Enable Sector Run. Thus, by depressing the alt or option key while choosing the Sector Specs... item from the Run menu, you can toggle between Run Selected Sectors and Run Entire Model without entering the Sector Specs... dialog.