Improve statistic handling

 - Add monitors to all basic model elements
 - Add name to monitors
 - Adapt more samples to make use of monitoring
 - Bug fixes

Author: abeham

Samples/BankRenege.cs

@@ -64,11 +64,20 @@ public void Simulate(int rseed = 41) {
       // Setup and start the simulation
       var start = new DateTime(2014, 2, 1);
       // Create an environment and start the setup process
-      var env = new Simulation(start, 41);
+      var env = new Simulation(start, rseed, defaultStep: TimeSpan.FromMinutes(1));
       env.Log("== Bank renege ==");
-      var counter = new Resource(env, capacity: 1);
+      var counter = new Resource(env, capacity: 1) {
+        BreakOffTime = new SampleMonitor(name: "BreakOffTime", collect: true),
+        Utilization = new TimeSeriesMonitor(env, name: "Utilization"),
+        WaitingTime = new SampleMonitor(name: "Waiting time", collect: true),
+        QueueLength = new TimeSeriesMonitor(env, name: "Queue Length", collect: true),
+      };
       env.Process(Source(env, counter));
       env.Run();
+      env.Log(counter.BreakOffTime.Summarize());
+      env.Log(counter.Utilization.Summarize());
+      env.Log(counter.WaitingTime.Summarize());
+      env.Log(counter.QueueLength.Summarize());
     }
   }
 }

Samples/GasStationRefueling.cs

@@ -70,14 +70,13 @@ private IEnumerable<Event> Car(string name, Simulation env, Resource gasStation,
         if (litersRequired > fuelPump.Level) {
           var level = fuelPump.Level;
           yield return fuelPump.Get(level); // draw it empty
+          yield return env.Timeout(TimeSpan.FromSeconds(level / RefuelingSpeed));
           yield return fuelPump.Get(litersRequired - level); // wait for the rest
+          yield return env.Timeout(TimeSpan.FromSeconds((litersRequired - level) / RefuelingSpeed));
         } else {
           yield return fuelPump.Get(litersRequired);
+          yield return env.Timeout(TimeSpan.FromSeconds(litersRequired / RefuelingSpeed));
         }
-
-        // The "actual" refueling process takes some time
-        yield return env.Timeout(TimeSpan.FromSeconds(litersRequired / RefuelingSpeed));
-
         env.Log("{0} finished refueling in {1} seconds.", name, (env.Now - start).TotalSeconds);
       }
     }
@@ -101,9 +100,8 @@ private IEnumerable<Event> TankTruck(Simulation env, Container fuelPump) {
       yield return env.Timeout(TankTruckTime);
       env.Log("Tank truck arriving at time {0}", env.Now);
       var amount = fuelPump.Capacity - fuelPump.Level;
-      env.Log("Tank truck refuelling {0} liters.", amount);
       yield return fuelPump.Put(amount);
-      env.Log("Tank truck finished at time {0}.", env.Now);
+      env.Log("Tank truck finished refuelling {0} liters at time {1}.", amount, env.Now);
     }
 
     private IEnumerable<Event> CarGenerator(Simulation env, Resource gasStation, Container fuelPump) {
@@ -121,13 +119,23 @@ public void Simulate(int rseed = RandomSeed) {
       // Create environment and start processes
       var env = new Simulation(DateTime.Now.Date, rseed);
       env.Log("== Gas Station refuelling ==");
-      var gasStation = new Resource(env, 2);
-      var fuelPump = new Container(env, GasStationSize, GasStationSize);
+      var gasStation = new Resource(env, 2) {
+        QueueLength = new TimeSeriesMonitor(env, name: "Waiting cars", collect: true),
+        WaitingTime = new SampleMonitor(name: "Waiting time", collect: true),
+        Utilization = new TimeSeriesMonitor(env, name: "Station utilization"),
+      };
+      var fuelPump = new Container(env, GasStationSize, GasStationSize) {
+        Fillrate = new TimeSeriesMonitor(env, name: "Tank fill rate")
+      };
       env.Process(GasStationControl(env, fuelPump));
       env.Process(CarGenerator(env, gasStation, fuelPump));
 
       // Execute!
       env.Run(SimTime);
+      env.Log(gasStation.QueueLength.Summarize());
+      env.Log(gasStation.WaitingTime.Summarize());
+      env.Log(gasStation.Utilization.Summarize());
+      env.Log(fuelPump.Fillrate.Summarize());
     }
   }
 }

Samples/KanbanControl.cs

@@ -59,11 +59,15 @@ public void Simulate() {
       env.Log("== Kanban controlled production system ==");
       kanban = new Resource(env, capacity: 15);
       server = new Resource(env, capacity: 1);
-      stockStat = new TimeSeriesMonitor(env);
+      // In this sample stockStat is tracked manually in the process
+      // it would also possible to track kanban's utilization and obtain
+      // the stock as capacity * (1 - util.mean)
+      stockStat = new TimeSeriesMonitor(env, name: "Kanbans in stock", collect: true);
       env.Process(Source());
       env.Run(TimeSpan.FromDays(180));
-      Console.WriteLine("Stock: {0} ; {1:F3}±{2:F3} ; {3} (Min;Mean±StdDev;Max) kanbans ", stockStat.Min, stockStat.Mean, stockStat.StdDev, stockStat.Max);
+      Console.WriteLine("Kanbans in stock: {0} ; {1:F1}±{2:F1} ; {3} (Min;Mean±StdDev;Max) kanbans ", stockStat.Min, stockStat.Mean, stockStat.StdDev, stockStat.Max);
       Console.WriteLine("Produced kanbans: {0:N0}", completedOrders);
+      Console.WriteLine(stockStat.Summarize(histInterval: 1));
     }
   }
 }

Samples/MM1Queueing.cs

@@ -47,10 +47,10 @@ public void Simulate() {
       var analyticWaitingtime = rho / (mu - lambda);
 
       var env = new Simulation(randomSeed: 1, defaultStep: TimeSpan.FromMinutes(1));
-      var utilization = new TimeSeriesMonitor(env);
-      var wip = new TimeSeriesMonitor(env, collect: true);
-      var leadtime = new SampleMonitor(collect: true);
-      var waitingtime = new SampleMonitor(collect: true);
+      var utilization = new TimeSeriesMonitor(env, name: "Utilization");
+      var wip = new TimeSeriesMonitor(env, name: "WIP", collect: true);
+      var leadtime = new SampleMonitor(name: "Lead time", collect: true);
+      var waitingtime = new SampleMonitor(name: "Waiting time", collect: true);
 
       env.Log("Analytical results of this system:");
       env.Log("\tUtilization.Mean\tWIP.Mean\tLeadtime.Mean\tWaitingTime.Mean");
@@ -75,6 +75,7 @@ public void Simulate() {
         .SetOutput(env.Logger)
         .SetSeparator("\t")
         .SetFinalUpdate(withHeaders: false) // creates a summary of the means at the end
+        .SetTimeAPI(useDApi: true)
         .Build();
 
       env.Log("Simulated results of this system:");
@@ -101,10 +102,10 @@ public void Simulate() {
       env.Log("");
       env.Log("Detailed results from the last run:");
       env.Log("");
-      env.Log(utilization.Print("Utilization"));
-      env.Log(wip.Print("WIP"));
-      env.Log(leadtime.Print("Lead time"));
-      env.Log(waitingtime.Print("Waiting time"));
+      env.Log(utilization.Summarize());
+      env.Log(wip.Summarize(maxBins: 10, histInterval: 2));
+      env.Log(leadtime.Summarize(maxBins: 10, histInterval: 5));
+      env.Log(waitingtime.Summarize(maxBins: 10, histInterval: 4));  ;
     }
   }
 }

Samples/RunAllSamples.cs

@@ -22,22 +22,22 @@ namespace SimSharp.Samples {
   class RunAllSamples {
     public static void Main(string[] args) {
       // Run all samples one after another
-      //new BankRenege().Simulate();
-      //Console.WriteLine();
-      //new GasStationRefueling().Simulate();
-      //Console.WriteLine();
-      //new MachineShop().Simulate();
-      //Console.WriteLine();
-      //new ProcessCommunication().Simulate();
-      //Console.WriteLine();
-      //new SteelFactory().Simulate();
-      //Console.WriteLine();
-      //new MachineShopSpecialist().Simulate();
-      //Console.WriteLine();
-      //new SimpleShop().Simulate();
-      //Console.WriteLine();
-      //new KanbanControl().Simulate();
-      //Console.WriteLine();
+      new BankRenege().Simulate();
+      Console.WriteLine();
+      new GasStationRefueling().Simulate();
+      Console.WriteLine();
+      new MachineShop().Simulate();
+      Console.WriteLine();
+      new ProcessCommunication().Simulate();
+      Console.WriteLine();
+      new SteelFactory().Simulate();
+      Console.WriteLine();
+      new MachineShopSpecialist().Simulate();
+      Console.WriteLine();
+      new SimpleShop().Simulate();
+      Console.WriteLine();
+      new KanbanControl().Simulate();
+      Console.WriteLine();
       new MM1Queueing().Simulate();
     }
   }

SimSharp/Analysis/IMonitor.cs

@@ -31,6 +31,8 @@ public interface IMonitor {
 
     double GetMedian();
     double GetPercentile(double p);
+
+    string Summarize();
 
     event EventHandler Updated;
   }

SimSharp/Analysis/SampleMonitor.cs

@@ -37,6 +37,12 @@ public sealed class SampleMonitor : ISampleMonitor {
     /// </summary>
     public bool Collect { get; }
 
+    /// <summary>
+    /// The name of the variable that is being monitored.
+    /// Used for output in <see cref="Summarize(bool, int, double?, double?)"/>.
+    /// </summary>
+    public string Name { get; set; }
+
     public int Count { get; private set; }
 
     public double Min { get; private set; }
@@ -97,7 +103,8 @@ private static double GetPercentile(IList<double> s, double p) {
       return s.OrderBy(x => x).Skip(k - 1).Take(2).Average();
     }
 
-    public SampleMonitor(bool collect = false) {
+    public SampleMonitor(string name = null, bool collect = false) {
+      Name = name;
       Collect = collect;
       if (collect) samples = new List<double>(64);
     }
@@ -137,16 +144,45 @@ private void OnUpdated() {
       Updated?.Invoke(this, EventArgs.Empty);
     }
 
-    public string Print(string name = null, double? histMin = null, double? histInterval = null) {
+    string IMonitor.Summarize() {
+      return Summarize();
+    }
+
+    /// <summary>
+    /// Provides a summary of the statistics in a certain format.
+    /// If the monitor is configured to collect data, it may also print a histogram.
+    /// </summary>
+    /// <param name="withHistogram">Whether to suppress the histogram.
+    /// This is only effective if <see cref="Collect"/> was set to true, otherwise
+    /// the data to produce the histogram is not available in the first place.</param>
+    /// <param name="maxBins">The maximum number of bins that should be used.
+    /// Note that the bin width and thus the number of bins is also governed by
+    /// <paramref name="histInterval"/> if it is defined.
+    /// This is only effective if <see cref="Collect"/> and <paramref name="withHistogram"/>
+    /// was set to true, otherwise the data to produce the histogram is not available
+    /// in the first place.</param>
+    /// <param name="histMin">The minimum for the histogram to start at or the sample
+    /// minimum in case the default (null) is given.
+    /// This is only effective if <see cref="Collect"/> and <paramref name="withHistogram"/>
+    /// was set to true, otherwise the data to produce the histogram is not available
+    /// in the first place.</param>
+    /// <param name="histInterval">The interval for the bins of the histogram or the
+    /// range (<see cref="Max"/> - <see cref="Min"/>) divided by the number of bins
+    /// (<paramref name="maxBins"/>) in case the default value (null) is given.
+    /// This is only effective if <see cref="Collect"/> and <paramref name="withHistogram"/>
+    /// was set to true, otherwise the data to produce the histogram is not available
+    /// in the first place.</param>
+    /// <returns>A formatted string that provides a summary of the statistics.</returns>
+    public string Summarize(bool withHistogram = true, int maxBins = 20, double? histMin = null, double? histInterval = null) {
       var nozero = Collect ? samples.Where(x => x != 0).ToList() : new List<double>();
       var nozeromin = nozero.Count > 0 ? nozero.Min() : double.NaN;
       var nozeromax = nozero.Count > 0 ? nozero.Max() : double.NaN;
       var nozeromean = nozero.Count > 1 ? nozero.Average() : double.NaN;
       var nozerostdev = nozero.Count > 2 ? Math.Sqrt(nozero.Sum(x => (x - nozeromean) * (x - nozeromean)) / (nozero.Count - 1.0)) : double.NaN;
       var sb = new StringBuilder();
       sb.Append("Statistics");
-      if (!string.IsNullOrEmpty(name))
-        sb.Append(" of " + name);
+      if (!string.IsNullOrEmpty(Name))
+        sb.Append(" of " + Name);
       sb.AppendLine();
       sb.AppendLine("                all             excl.zero       zero           ");
       sb.AppendLine("--------------- --------------- --------------- ---------------");
@@ -162,19 +198,20 @@ public string Print(string name = null, double? histMin = null, double? histInte
       }
       sb.AppendLine(string.Format("{0,15} {1,15} {2,15}", "Maximum", Formatter.Format15(Max), Formatter.Format15(nozeromax)));
 
-      if (Collect) {
+      if (Collect && withHistogram) {
         var min = histMin ?? Min;
-        var interval = histInterval ?? (Max - Min) / 20.0;
-        var histData = samples.GroupBy(x => (int)Math.Floor(Math.Max(x - min + interval, 0) / interval))
-                           .ToDictionary(x => x.Key, x => x.Count());
+        var interval = histInterval ?? (Max - Min) / maxBins;
+        var histData = samples.GroupBy(x => x <= min ? 0 : (int)Math.Floor(Math.Min((x - min + interval) / interval, maxBins)))
+                           .Select(x => new { Key = x.Key, Value = x.Count() })
+                           .OrderBy(x => x.Key);
         sb.AppendLine();
         sb.AppendLine("Histogram");
         sb.AppendLine("<=              count      %     cum%   ");
         sb.AppendLine("--------------- ---------- ----- ------");
         var cumul = 0.0;
         var totStars = 0;
         var last = -1;
-        foreach (var kvp in histData.OrderBy(x => x.Key)) {
+        foreach (var kvp in histData) {
           while (kvp.Key > last + 1) {
             last++;
             var tmp = "|".PadLeft(totStars + 1);
@@ -189,7 +226,9 @@ public string Print(string name = null, double? histMin = null, double? histInte
           var stars = string.Join("", Enumerable.Repeat("*", numstars));
           totStars += numstars;
           var cumulbar = "|".PadLeft(totStars + 1 - numstars);
-          sb.AppendLine(string.Format("{0,15} {1,10} {2,5:F1} {3,5:F1} {4}{5}", Formatter.Format15(min + kvp.Key * interval), kvp.Value, prob * 100, cumul * 100, stars, cumulbar));
+          sb.AppendLine(string.Format("{0,15} {1,10} {2,5:F1} {3,5:F1} {4}{5}",
+            (kvp.Key == maxBins && min + kvp.Key * interval < Max) ? "inf" : Formatter.Format15(min + kvp.Key * interval),
+            kvp.Value, prob * 100, cumul * 100, stars, cumulbar));
           last = kvp.Key;
         }
       }