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""" bank10: 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))
activate(c, c.visit(counters))
t = expovariate(1.0 / interval)
yield hold, self, t
def NoInSystem(R): # (1)
""" Total number of customers in the resource R"""
return (len(R.waitQ) + len(R.activeQ)) # (2)
class Customer(Process):
""" Customer arrives, chooses the shortest queue
is served and leaves
"""
def visit(self, counters):
arrive = now()
Qlength = [NoInSystem(counters[i]) for i in range(Nc)] # (3)
print("%7.4f %s: Here I am. %s" % (now(), self.name, Qlength)) # (4)
for i in range(Nc): # (5)
if Qlength[i] == 0 or Qlength[i] == min(Qlength):
choice = i # the index of the shortest line
break # (6)
yield request, self, counters[choice]
wait = now() - arrive
print("%7.4f %s: Waited %6.3f" % (now(), self.name, wait))
tib = expovariate(1.0 / timeInBank)
yield hold, self, tib
yield release, self, counters[choice]
print("%7.4f %s: Finished" % (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 = 787878
## Model/Experiment ------------------------------
seed(theseed)
kk = [Resource(name="Clerk0"), Resource(name="Clerk1")] # (7)
initialize()
s = Source('Source')
activate(s, s.generate(number=maxNumber, interval=ARRint,
counters=kk), at=0.0)
simulate(until=maxTime)
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