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""" bank11.py: Simulate customers arriving
at random, using a Source, requesting service
from two counters each with their own queue
random servicetime.
Uses a Monitor object to record waiting times
"""
from SimPy.Simulation import *
from SimPy.SimPlot import *
from random import Random
class Bank11(SimPlot):
def __init__(self,**p):
SimPlot.__init__(self,**p)
def NoInSystem(self,R):
""" The number of customers in the resource R
in waitQ and active Q"""
return (len(R.waitQ)+len(R.activeQ))
def model(self):
self.counterRV = Random(self.params["counterseed"])
self.sourceseed = self.params["sourceseed"]
nrRuns=self.params["nrRuns"]
self.lastLeave=0
self.noRunYet=True
for runNr in range(nrRuns):
self.noRunYet=False
self.Nc = 2
self.counter = [Resource(name="Clerk0",monitored=False),
Resource(name="Clerk1",monitored=False)]
self.waitMonitor = Monitor(name='Waiting Times')
self.waitMonitor.xlab='Time'
self.waitMonitor.ylab='Waiting time'
self.serviceMonitor = Monitor(name='Service Times')
self.serviceMonitor.xlab='Time'
self.serviceMonitor.ylab='wait+service'
initialize()
source = Source(self,seed = self.sourceseed*1000)
activate(source,source.generate(self.params["numberCustomers"],
self.params["interval"]),0.0)
simulate(until=self.params['endtime'])
self.lastLeave+=now()
print "%s run(s) completed"%(nrRuns)
print("Parameters:\n%s"%self.params)
class Source(Process):
""" Source generates customers randomly"""
def __init__(self,modInst,seed=333):
Process.__init__(self)
self.modInst=modInst
self.SEED = seed
def generate(self,number,interval):
rv = Random(self.SEED)
for i in range(number):
c = Customer(self.modInst,name = "Customer%02d"%(i,))
activate(c,c.visit(timeInBank=12.0))
t = rv.expovariate(1.0/interval)
yield hold,self,t
class Customer(Process):
""" Customer arrives, is served and leaves """
def __init__(self,modInst,**p):
Process.__init__(self,**p)
self.modInst=modInst
def visit(self,timeInBank=0):
arrive=now()
Qlength = [self.modInst.NoInSystem(self.modInst.counter[i])\
for i in range(self.modInst.Nc)]
for i in range(self.modInst.Nc):
if Qlength[i] ==0 or Qlength[i]==min(Qlength): join =i ; break
yield request,self,self.modInst.counter[join]
wait=now()-arrive
self.modInst.waitMonitor.observe(wait,t=now())
##print "%7.4f %s: Waited %6.3f"%(now(),self.name,wait)
tib = self.modInst.counterRV.expovariate(1.0/timeInBank)
yield hold,self,tib
yield release,self,self.modInst.counter[join]
self.modInst.serviceMonitor.observe(now()-arrive,t=now())
root=Tk()
plt=Bank11()
plt.params={"endtime":2000,
"sourceseed":1133,
"counterseed":3939393,
"numberCustomers":50,
"interval":10.0,
"trace":0,
"nrRuns":1}
plt.model()
plt.plotLine(plt.waitMonitor,color='blue',width=2)
plt.plotLine(plt.serviceMonitor,color='red',width=2)
root.mainloop()
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