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""" bank10_OO: Several Counters with individual queues"""
from SimPy.Simulation import Simulation, Process, Resource, hold, request, release
from random import expovariate, seed
## Model components ------------------------
class Source(Process):
""" Source generates customers randomly"""
def generate(self, number, interval):
for i in range(number):
c = Customer(name="Customer%02d" % (i,), sim=self.sim)
self.sim.activate(c, c.visit(counters=self.sim.kk))
t = expovariate(1.0 / interval)
yield hold, self, t
def NoInSystem(R):
""" Total number of customers in the resource R"""
return (len(R.waitQ) + len(R.activeQ))
class Customer(Process):
""" Customer arrives, chooses the shortest queue
is served and leaves
"""
def visit(self, counters):
arrive = self.sim.now()
Qlength = [NoInSystem(counters[i]) for i in range(Nc)]
print("%7.4f %s: Here I am. %s" % (self.sim.now(), self.name, Qlength))
for i in range(Nc):
if Qlength[i] == 0 or Qlength[i] == min(Qlength):
choice = i # the chosen queue number
break
yield request, self, counters[choice]
wait = self.sim.now() - arrive
print("%7.4f %s: Waited %6.3f" % (self.sim.now(), self.name, wait))
tib = expovariate(1.0 / timeInBank)
yield hold, self, tib
yield release, self, counters[choice]
print("%7.4f %s: Finished" % (self.sim.now(), self.name))
## Model -----------------------------------
class BankModel(Simulation):
def run(self, aseed):
""" PEM """
seed(aseed)
self.kk = [Resource(name="Clerk0", sim=self),
Resource(name="Clerk1", sim=self)]
s = Source('Source', sim=self)
self.activate(s, s.generate(number=maxNumber, interval=ARRint), at=0.0)
self.simulate(until=maxTime)
## Experiment data -------------------------
maxNumber = 5
maxTime = 400.0 # minutes
timeInBank = 12.0 # mean, minutes
ARRint = 10.0 # mean, minutes
Nc = 2 # number of counters
seedVal = 787878
## Experiment ------------------------------
mymodel = BankModel()
mymodel.run(aseed=seedVal)
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