Add queueing example model

examples/queueing/experiment.py

@@ -0,0 +1,45 @@
+from pypdevs.simulator import Simulator
+import random
+
+# Import the model we experiment with
+from system import QueueSystem
+
+# Configuration:
+# 1) number of customers to simulate
+num = 500
+# 2) average time between two customers
+time = 30.0
+# 3) average size of customer
+size = 20.0
+# 4) efficiency of processors (products/second)
+speed = 0.5
+# 5) maximum number of processors used
+max_processors = 10
+# End of configuration
+
+# Store all results for output to file
+values = []
+# Loop over different configurations
+for i in range(1, max_processors):
+    # Make sure each of them simulates exactly the same workload
+    random.seed(1)
+    # Set up the system
+    procs = [speed] * i
+    m = QueueSystem(mu=1.0/time, size=size, num=num, procs=procs)
+
+    # PythonPDEVS specific setup and configuration
+    sim = Simulator(m)
+    sim.setClassicDEVS()
+    sim.simulate()
+
+    # Gather information for output
+    evt_list = m.collector.state.events
+    values.append([e.queueing_time for e in evt_list])
+
+# Write data to file
+with open('output.csv', 'w') as f:
+    for i in range(num):
+        f.write("%s" % i)
+        for j in range(len(values)):
+            f.write(", %5f" % (values[j][i]))
+        f.write("\n")