""" bank10_OO: Several Counters with individual queues"""
from SimPy.Simulation import *
from random import expovariate,seed
## Model components ------------------------
class Source(Process):
""" Source generates customers randomly"""
def generate(self,number,interval,counters):
for i in range(number):
c = Customer(name = "Customer%02d"%(i,),sim=self.sim)
self.sim.activate(c,c.visit(counters))
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)
## Experiment data -------------------------
maxNumber = 5
maxTime = 400.0 # minutes
timeInBank = 12.0 # mean, minutes
ARRint = 10.0 # mean, minutes
Nc = 2 # number of counters
theseed = 12345
## Model -----------------------------------
class BankModel(Simulation):
def run(self):
self.initialize()
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,
counters=kk),at=0.0)
self.simulate(until=maxTime)
## Experiment ------------------------------
seed(theseed)
BankModel().run()
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