""" bank12: Multiple runs of the bank with a Monitor"""
from SimPy.Simulation import *
from random import expovariate,seed
## Model components ------------------------
class Source(Process):
""" Source generates customers randomly"""
def generate(self,number,interval,resource,mon):
for i in range(number):
c = Customer(name = "Customer%02d"%(i,))
activate(c,c.visit(b=resource,M=mon))
t = expovariate(1.0/interval)
yield hold,self,t
class Customer(Process):
""" Customer arrives, is served and leaves """
def visit(self,b,M):
arrive = now()
yield request,self,b
wait = now()-arrive
M.observe(wait)
tib = expovariate(1.0/timeInBank)
yield hold,self,tib
yield release,self,b
## Experiment data -------------------------
maxNumber = 50
maxTime = 2000.0 # minutes
timeInBank = 12.0 # mean, minutes
ARRint = 10.0 # mean, minutes
Nc = 2 # number of counters
theSeed = 393939
## Model ----------------------------------
def model(runSeed=theSeed):
seed(runSeed)
k = Resource(capacity=Nc,name="Clerk")
wM = Monitor()
initialize()
s = Source('Source')
activate(s,s.generate(number=maxNumber,interval=ARRint,
resource=k,mon=wM),at=0.0)
simulate(until=maxTime)
return (wM.count(),wM.mean())
## Experiment/Result ----------------------------------
theseeds = [393939,31555999,777999555,319999771]
for Sd in theseeds:
result = model(Sd)
print "Average wait for %3d completions was %6.2f minutes."% result
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