不能在 SIMPY 中触发两个事件python 中的模拟

问题描述

最近我了解了 SIMPY，我认为它可以为我的工作提供一些信息并提供决策背景非常有帮助。请注意，我是 Python 编程的新手，我知道基础知识，但我正在学习。

问题： 我在一个集装箱码头工作，我们有三种类型的移动：

与船只相关的移动（大约每 120 秒产生一次移动。）
与仓库相关的移动（大约每 960 秒生成一次移动。）
与门相关的移动（大约每 800 秒生成一次移动。）

所有这些动作都是在所描述的时间间隔内同时“生成”的。船舶和仓库都有自己的运输工具。但是，上述所有步骤的目标都是相同的。容器堆栈采用 FIFO 原则（先进先出），一次可以处理四个移动。一个动作大约需要 270 秒。

我想要实现的是通过改变资源量（船只和仓库和闸门移动的运输数量）来查看对集装箱堆内业务的影响。

我获得了适用于其中一个流程 (VESSEL) 的基本模拟，现在我正在尝试添加仓库流程，但是我卡住了。当我使用以下代码时，只会生成来自船只的移动：

def move_generator(env):

    while True:
        yield env.timeout(120)
        print("Vessel move generated at: %.1f" % (env.Now))

    while True:
        yield env.timeout(960)
        print("Warehouse move generated at: %.1f" % (env.Now)) 


import simpy
env = simpy.Environment()
env.process(move_generator(env))
    
env.run(until=3600)

以上代码的输出为：

Vessel move generated at: 120.0
Vessel move generated at: 240.0
Vessel move generated at: 360.0
Vessel move generated at: 480.0
Vessel move generated at: 600.0
Vessel move generated at: 720.0
Vessel move generated at: 840.0
Vessel move generated at: 960.0
Vessel move generated at: 1080.0
Vessel move generated at: 1200.0
Vessel move generated at: 1320.0
Vessel move generated at: 1440.0
Vessel move generated at: 1560.0
Vessel move generated at: 1680.0
Vessel move generated at: 1800.0
Vessel move generated at: 1920.0
Vessel move generated at: 2040.0
Vessel move generated at: 2160.0
Vessel move generated at: 2280.0
Vessel move generated at: 2400.0
Vessel move generated at: 2520.0
Vessel move generated at: 2640.0
Vessel move generated at: 2760.0
Vessel move generated at: 2880.0
Vessel move generated at: 3000.0
Vessel move generated at: 3120.0
Vessel move generated at: 3240.0
Vessel move generated at: 3360.0
Vessel move generated at: 3480.0

但是所需的输出是：

Vessel move generated at: 120.0
Vessel move generated at: 240.0
Vessel move generated at: 360.0
Vessel move generated at: 480.0
Vessel move generated at: 600.0
Vessel move generated at: 720.0
Vessel move generated at: 840.0
Vessel move generated at: 960.0
Warehouse move generated at: 960.0
Vessel move generated at: 1080.0
Vessel move generated at: 1200.0
Vessel move generated at: 1320.0
Vessel move generated at: 1440.0
Vessel move generated at: 1560.0
Vessel move generated at: 1680.0
Vessel move generated at: 1800.0
Vessel move generated at: 1920.0
Warehouse move generated at: 1920.0
Vessel move generated at: 2040.0
Vessel move generated at: 2160.0
Vessel move generated at: 2280.0
Vessel move generated at: 2400.0
Vessel move generated at: 2520.0
Vessel move generated at: 2640.0
Vessel move generated at: 2760.0
Vessel move generated at: 2880.0
Warehouse move generated at: 2880.0
Vessel move generated at: 3000.0
Vessel move generated at: 3120.0
Vessel move generated at: 3240.0
Vessel move generated at: 3360.0
Vessel move generated at: 3480.0

我认为问题出在两个 while True 语句中，但我不知道如何正确处理。我一直在使用 Google（可能不知道找到答案的正确术语）但没有成功。

解决方法

正如您在评论中指出的，问题在于您使用的是 python，而不是 simpy。

while True:
  <do anything>

# already unreachable
while True:
  # also unreachable

对于您的示例，请尝试查看 https://simpy.readthedocs.io/en/latest/simpy_intro/shared_resources.html

for i in range(4):
    env.process(car(env,'Car %d' % i,bcs,i*2,5))
env.run()

您可以看到 process 可以在 run 之前多次调用，从而允许您按照自己的意愿进行“并行”工作。

import simpy


def vessel(env):
    while True:
        yield env.timeout(120)
        print("Vessel move generated at: %.1f" % (env.now))


def warehouse(env):
    while True:
        yield env.timeout(960)
        print("Warehouse move generated at: %.1f" % (env.now)) 


def main():
    env = simpy.Environment()
    env.process(vessel(env))
    env.process(warehouse(env))
    env.run(until=3600)

if __name__ == '__main__':
    main()

这给了

Vessel move generated at: 120.0
Vessel move generated at: 240.0
Vessel move generated at: 360.0
Vessel move generated at: 480.0
Vessel move generated at: 600.0
Vessel move generated at: 720.0
Vessel move generated at: 840.0
Warehouse move generated at: 960.0
Vessel move generated at: 960.0
Vessel move generated at: 1080.0
Vessel move generated at: 1200.0
Vessel move generated at: 1320.0
Vessel move generated at: 1440.0
Vessel move generated at: 1560.0
Vessel move generated at: 1680.0
Vessel move generated at: 1800.0
Warehouse move generated at: 1920.0
Vessel move generated at: 1920.0
Vessel move generated at: 2040.0
Vessel move generated at: 2160.0
Vessel move generated at: 2280.0
Vessel move generated at: 2400.0
Vessel move generated at: 2520.0
Vessel move generated at: 2640.0
Vessel move generated at: 2760.0
Warehouse move generated at: 2880.0
Vessel move generated at: 2880.0
Vessel move generated at: 3000.0
Vessel move generated at: 3120.0
Vessel move generated at: 3240.0
Vessel move generated at: 3360.0
Vessel move generated at: 3480.0

event-simulation python simpy simulation