banking.py

""" bank09: Several Counters but a Single Queue """
from SimPy.Simulation import *
from random import expovariate, seed

## Model components ------------------------           

class Source(Process):
    """ Source generates customers randomly """

    def generate(self,number,meanTBA,resource):      
        for i in range(number):
            c = Customer(name = "Customer%02d"%(i,))
            activate(c,c.visit(b=resource))            
            t = expovariate(1.0/meanTBA)              
            yield hold,self,t

class Customer(Process):
    """ Customer arrives, is served and leaves """
        
    def visit(self,b):                                
        arrive = now()
        print "%8.4f %s: Here I am     "%(now(),self.name)
        yield request,self,b                          
        wait = now()-arrive
        print "%8.4f %s: Waited %6.3f"%(now(),self.name,wait)
        tib = expovariate(1.0/timeInBank)            
        yield hold,self,tib                          
        yield release,self,b                         
        print "%8.4f %s: Finished      "%(now(),self.name)

## Experiment data -------------------------         

maxNumber = 5
maxTime = 400.0 # minutes                                      
timeInBank = 12.0 # mean, minutes                      
ARRint = 10.0   # mean, minutes                      
theseed = 12345                                        

## Model/Experiment ------------------------------

seed(theseed)                                        
k = Resource(capacity=2,name="Counter",unitName="Clerk")  

initialize()
s = Source('Source')
activate(s, s.generate(number=maxNumber,meanTBA=ARRint, 
                         resource=k),at=0.0)           
simulate(until=maxTime)