Transducer

Figure 4.7: State Transition Diagrams of Transducer

Transducer's behavior is pretty much opposite to that of Generator. Figure 4.7 shows its state transition diagram. It has an input port iin and a buffer Collector as Dictionary<int, List<Job>> to collect jobs coming in with respect to their types.

public class Transducer: Atomic
    {
        public InputPort iin;
        Dictionary<int, List<Job>> Collector;

        public Transducer(string name, TimeUnit tu): base(name, tu)
        {
            CollectStatistics(true); // default collecting statistics
            iin = AddIP("in");
            Collector = new Dictionary<int, List<Job>>();
        }

Transducer::init() clears all clients in Collector. Transducer::tau() returns $\infty$ all the time so it is passive.

    public override void init() { Collector.Clear(); }
    public override double tau() { return double.MaxValue; }

Transducer::delta_x() castes the input value x.value to pv of Job type. It stamps pv with (``SysOut'',CurrentTime), and pushes pv into Collector. Since Transducer is always passive, it has no output, and so delta_y() is not needed here;

    public override bool delta_x(PortValue x)
    {
        Job pv = (Job) x.value;
        if(pv != null)
        {
            //-- (event, time) stamping
            pv.TimeMap.Add("SysOut", Devs.TimeCurrent);
            if (Collector.ContainsKey(pv.type) == false)
                Collector.Add(pv.type, new List<Job>());
            Collector[pv.type].Add(pv);
        }
        //else
        //    throw new Exception("Type casting Failed!");
        return false;
    }

Recall that Transducer collects incoming Jobs stamped with (``SysIn'',arrival-time) by Generator, (``SysOut'',departure-time) by Transducer. Using these data, GetPerformance() of Transducers returns {(``Throughput'', value) and (``Average System Time'', value) } as follows.

• Average Throughput value defined in Equation (4.1) is the number of Jobs in Collector divided by the current time that is the observation time-length $t_o$ of a simulation run.
• Average System Time defined in Equation (4.2) is the average value of all time durations (arrival-time, departure-time) for each Job in Collector.

• In addition, even though the number of jobs went through the system can be recalculated by Average Throughput, it will be displayed by counting the jobs collected into Transducer in terms of their job types.

The function Transducer::GetPerformance() returns these three indices. The source code of GetPerformance() is available in Transducer.cs.