1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
"""
Movie_renege
Demo program to show event-based reneging by
'yield (request,self,res),(waitevent,self,evt)'.
Scenario:
A movie theatre has one ticket counter selling tickets for
three movies (next show only). When a movie is sold out, all
people waiting to buy ticket for that movie renege (leave queue).
"""
from SimPy.Simulation import *
from random import *
## Model components ------------------------
class MovieGoer(Process):
def getTickets(self,whichMovie,nrTickets):
yield (request,self,ticketCounter),(waitevent,self,soldOut[whichMovie])
if self.acquired(ticketCounter):
if available[whichMovie]>=nrTickets:
available[whichMovie]-=nrTickets
if available[whichMovie]<2:
soldOut[whichMovie].signal()
whenSoldOut[whichMovie]=now()
available[whichMovie]=0
yield hold,self,1
else:
yield hold,self,0.5
yield release,self,ticketCounter
else:
nrRenegers[whichMovie]+=1
class CustomerArrivals(Process):
def traffic(self):
while now()<120:
yield hold,self,expovariate(1/0.5)
movieChoice=choice(movies)
nrTickets=randint(1,6)
if available[movieChoice]:
m=MovieGoer()
activate(m,m.getTickets(whichMovie=movieChoice,nrTickets=nrTickets))
## Experiment data -------------------------
seed(111333555)
movies=["Gone with the Windows","Hard Core Dump","Modern CPU Times"]
available={}
soldOut={}
nrRenegers={}
whenSoldOut={}
for film in movies:
available[film]=50
soldOut[film]=SimEvent(film)
nrRenegers[film]=0
ticketCounter=Resource(capacity=1)
## Model/Experiment ------------------------------
print 'Movie_renege'
initialize()
c=CustomerArrivals()
activate(c,c.traffic())
simulate(until=120)
for f in movies:
if soldOut[f]:
print "Movie '%s' sold out %.0f minutes after ticket counter opening."%(f,int(whenSoldOut[f]))
print "\tNr people leaving queue when film '%s' sold out: %s"%(f,nrRenegers[f])
|
