Add queueing example model

examples/queueing/system.py

@@ -0,0 +1,33 @@
+from pypdevs.DEVS import CoupledDEVS
+
+# Import all models to couple
+from generator import Generator
+from queue import Queue
+from processor import Processor
+from collector import Collector
+
+class QueueSystem(CoupledDEVS):
+    def __init__(self, mu, size, num, procs):
+        CoupledDEVS.__init__(self, "QueueSystem")
+
+        # Define all atomic submodels of which there are only one
+        generator = self.addSubModel(Generator(mu, size, num))
+        queue = self.addSubModel(Queue(len(procs)))
+        collector = self.addSubModel(Collector())
+
+        self.connectPorts(generator.out_event, queue.in_event)
+
+        # Instantiate desired number of processors and connect
+        processors = []
+        for i, param in enumerate(procs):
+            processors.append(self.addSubModel(
+                              Processor(i, param)))
+            self.connectPorts(queue.out_proc[i],
+                              processors[i].in_proc)
+            self.connectPorts(processors[i].out_finished,
+                              queue.in_finish)
+            self.connectPorts(processors[i].out_proc,
+                              collector.in_event)
+
+        # Make it accessible outside of our own scope
+        self.collector = collector