我想创建一个模拟具有3个计数器的银行的模拟模型。我希望客户有一个队列，如果有任何一个计数器可用，它将为计数器服务一段时间。每个计数器都是它自己的简单资源（我不能做一个容量为3的资源），我需要知道哪个计数器服务于客户。我无法实现这一点。
我发现这篇文章似乎有同样的问题，但仍然不知道确切的实现http://comments.gmane.org/gmane.comp.python.simpy.user/1754
我假设我需要一个yield simpy.AnyOf（env，list_of_resources）来请求第一个可用的计数器，但我无法弄清楚如何正确设置它，以及如果同时有多个资源可用时间，我想要一些方法来检查这个，这样我就可以选择哪个柜台更适合顾客去。
我正在运行python版本2.7，简化版本3.0.4
编辑添加代码，显示我正在尝试做什么以及它现在无法正常工作。
import simpy
import random
LENGTH_SIM = 200.0
class Customer(object):
def __init__(self, arrive_time, num):
self.arrive_time = arrive_time
self.start_service_time = -1.0
self.finish_service_time = -1.0
self.served_by = -1.0
self.num = num
def print_attributes(self):
format_string = "#%3d Arrive: %6.1f Start Service: %6.1f "\
+ " End Service: %6.1f" + " Served By: %3d"
print format_string %(self.num, self.arrive_time,
self.start_service_time,
self.finish_service_time, self.served_by)
class Counter(object):
def __init__(self, number):
self.number = number
self.name = "Counter " + str(number)
self.start_times = []
self.end_times = []
class Bank(object):
def __init__(self, env, num_counters):
self.counters = [Counter(x+1) for x in range(num_counters)]
self.num_counters = num_counters
self.counters_resources = [simpy.Resource(env, capacity=1)
for x in range(num_counters)]
def generate_customers(env, customers):
count = 1
while 1:
wait_time = random.randint(8, 12)
yield env.timeout(wait_time)
customers.append(Customer(env.now, count))
print "Generated Customer: ", count
count += 1
def select_counter(env, bank):
'''choose a counter for the customer'''
for x in range(len(bank.counters)):
if bank.counters_resources[len(bank.counters) - 1 - x].count == 0:
print "Counter Selected: ", len(bank.counters) - 1 - x
print bank.counters[len(bank.counters) - 1 - x].number
print bank.counters_resources[len(bank.counters) - 1 - x].users
return len(bank.counters) - 1 - x
return -2.0
def gen_service_time():
return random.random() * 20.0 + 21.0
def handle_customer(env, bank, customer, customers, num_process):
'''handles customer'''
print "Process ", num_process, " started at:", env.now
counter = select_counter(env, bank)
print "Process ", num_process, " after counter select:", env.now
if counter != -2.0:
with bank.counters_resources[counter].request() as req:
yield req
print "Process ", num_process, "Time", env.now, "In if"
bank.counters[counter].start_times.append(env.now)
service_time = gen_service_time()
customer.start_service_time = env.now
customer.finish_service_time = env.now + service_time
bank.counters[counter].end_times.append(env.now + service_time)
customer.served_by = counter + 1
yield env.timeout(service_time)
else:
reqs = []
for x in range(len(bank.counters)):
reqs.append(bank.counters_resources[x].request())
counter_used = yield simpy.events.AnyOf(env, reqs)
for x in range(len(reqs)):
if counter_used.keys()[0] != reqs[x]:
print "True"
bank.counters_resources[x].release(reqs[x])
print "Process ", num_process, "Time", env.now, "In else"
bank.counters[0].start_times.append(env.now)
service_time = gen_service_time()
customer.start_service_time = env.now
customer.finish_service_time = env.now + service_time
bank.counters[0].end_times.append(env.now + service_time)
customer.served_by = 1
yield env.timeout(service_time)
for x in range(len(reqs)):
## if counter_used.keys()[0] == reqs[x]:
if 1:
bank.counters_resources[x].release(reqs[x])
def run_bank(env, bank, customers):
while 1:
min_time = -1.0
min_customer = -1.0
for x in xrange(len(customers)):
if customers[x].arrive_time < min_time or min_time == -1.0:
if customers[x].arrive_time > env.now:
min_time = customers[x].arrive_time
min_customer = x
else:
continue
if min_time == -1.0:
yield env.timeout(LENGTH_SIM - env.now)
yield env.timeout(min_time - env.now)
print "Calling Process: ", min_customer, "At time:", env.now
env.process(handle_customer(env,bank,customers[min_customer],customers,
min_customer + 1))
def run_sim():
env = simpy.Environment()
customers = []
env.process(generate_customers(env, customers))
env.run(until=LENGTH_SIM)
env2 = simpy.Environment()
bank = Bank(env2, 3)
env2.process(run_bank(env2, bank, customers))
env2.run(until = LENGTH_SIM)
for x in range(len(customers)):
customers[x].print_attributes()
if __name__ == '__main__':
run_sim()
答案 0 :(得分：1)
如果您真的无法使用容量为3的普通资源，那么Store可能会对您有所帮助。商店存储您可以请求的计数器对象。每个计数器都有自己的标识，例如，可以跟踪其使用次数。客户完成后，必须将计数器放回商店：
import simpy
class Counter:
usages = 0
def customer(env, counters):
counter = yield counters.get()
yield env.timeout(1)
counter.usages += 1
yield counters.put(counter)
env = simpy.Environment()
counters = simpy.Store(env, capacity=3)
counters.items = [Counter() for i in range(counters.capacity)]
for i in range(10):
env.process(customer(env, counters))
env.run()
for counter in counters.items:
print(counter.usages)
答案 1 :(得分：0)
我自己设法解决了这个问题，我唯一不理解的是取消方法的不同参数是什么（我只是将它们全部设置为无，它可以工作，我不确定哪里有文档除了他们的名字，他们是什么）。固定代码如下（相关部分是handle_customer函数中的else子句：
import simpy
import random
LENGTH_SIM = 100.0
class Customer(object):
def __init__(self, arrive_time, num):
self.arrive_time = arrive_time
self.start_service_time = -1.0
self.finish_service_time = -1.0
self.served_by = -1.0
self.num = num
def print_attributes(self):
format_string = "#%3d Arrive: %6.1f Start Service: %6.1f "\
+ " End Service: %6.1f" + " Served By: %3d"
print format_string %(self.num, self.arrive_time,
self.start_service_time,
self.finish_service_time, self.served_by)
class Counter(object):
def __init__(self, number):
self.number = number
self.name = "Counter " + str(number)
self.start_times = []
self.end_times = []
class Bank(object):
def __init__(self, env, num_counters):
self.counters = [Counter(x+1) for x in range(num_counters)]
self.num_counters = num_counters
self.counters_resources = [simpy.Resource(env, capacity=1)
for x in range(num_counters)]
def generate_customers(env, customers):
count = 1
while 1:
## wait_time = random.randint(8, 12)
wait_time = 2
yield env.timeout(wait_time)
customers.append(Customer(env.now, count))
print "Generated Customer: ", count
count += 1
def select_counter(env, bank):
'''choose a counter for the customer'''
for x in range(len(bank.counters)):
if bank.counters_resources[len(bank.counters) - 1 - x].count == 0 and\
bank.counters_resources[len(bank.counters) - 1 - x].queue == []:
print "Counter Selected: ", len(bank.counters) - 1 - x
return len(bank.counters) - 1 - x
return -2.0
def gen_service_time():
## return random.random() * 20.0 + 19.0
return random.randint(4, 8)
def wait_til_available(env, bank, temp_list):
while 1:
yield env.timeout(0.0001)
for x in range(len(bank.counters)):
if bank.counters_resources[x].count == 0:
req = bank.counters_resources[x].request()
temp_list[0] = x
temp_list[1] = req
return
def handle_customer(env, bank, customer, customers, num_process):
'''handles customer'''
print "Process ", num_process, " started at:", env.now
counter = select_counter(env, bank)
if counter != -2.0:
with bank.counters_resources[counter].request() as req:
yield req
bank.counters[counter].start_times.append(env.now)
service_time = gen_service_time()
customer.start_service_time = env.now
customer.finish_service_time = env.now + service_time
bank.counters[counter].end_times.append(env.now + service_time)
customer.served_by = counter + 1
yield env.timeout(service_time)
else:
reqs = []
got_counter = 0
for x in range(len(bank.counters)):
reqs.append(bank.counters_resources[x].request())
good_req = yield simpy.events.AnyOf(env, reqs)
req = good_req.keys()[0]
for x in range(len(bank.counters)):
if req != reqs[x]:
bank.counters_resources[x].release(reqs[x])
reqs[x].cancel(None, None, None)
else:
got_counter = x
bank.counters[got_counter].start_times.append(env.now)
service_time = gen_service_time()
customer.start_service_time = env.now
customer.finish_service_time = env.now + service_time
bank.counters[got_counter].end_times.append(env.now + service_time)
customer.served_by = got_counter + 1
yield env.timeout(service_time)
print "Process ", num_process, " finished at:", env.now
bank.counters_resources[got_counter].release(req)
def run_bank(env, bank, customers):
while 1:
min_time = -1.0
min_customer = -1.0
for x in xrange(len(customers)):
if customers[x].arrive_time < min_time or min_time == -1.0:
if customers[x].arrive_time > env.now:
min_time = customers[x].arrive_time
min_customer = x
else:
continue
if min_time == -1.0:
yield env.timeout(LENGTH_SIM - env.now)
yield env.timeout(min_time - env.now)
print "Calling Process: ", min_customer+1, "At time:", env.now
env.process(handle_customer(env,bank,customers[min_customer],customers,
min_customer + 1))
def run_sim():
env = simpy.Environment()
customers = []
env.process(generate_customers(env, customers))
env.run(until=LENGTH_SIM)
env2 = simpy.Environment()
bank = Bank(env2, 3)
env2.process(run_bank(env2, bank, customers))
env2.run(until = LENGTH_SIM)
for x in range(len(customers)):
customers[x].print_attributes()
if __name__ == '__main__':
run_sim()