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A conditional event (ConditionalEvent.class) is an event that is performed when a specified condition is satisfied. A normal event (Event.class) is scheduled at a specified future simulation time.
Most simulation software packages provide a way to specify conditional events. The standard algorithm is to execute all the normal events for the next simulation time until none are left and then check the conditions for the conditional events. If any of the conditional events are executed, the conditions are re-tested. Once none of the conditional events are executed, the simulation advances to the event time for the next normal event.
Harry