There is a process/delay block which should process agents with different timings, how do I perform this?
Initially I thought I could assign a parameter and change this for each agent, and the delay block would process agents according to time specified in Parameter.
If the delay depends on each agent, you need to create an agent type in which you add a parameter, let's say you call it delayTime. Then, you can access this parameter in the flow charts by calling
agent.delayTime;
You can write the above in the delay time field of the delay block.
Check:
https://help.anylogic.com/topic/com.anylogic.help/html/processmodeling/agent-type.html?resultof=%22%63%75%73%74%6f%6d%22%20%22%61%67%65%6e%74%22%20%22%74%79%70%65%22%20
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I am building a model where at any point in time if any agent is in system beyond threshold it has to go to Sink block. Is it possible to do it based on Agent time in system ?
If agents spent 180 days and beyond I want to send it to write-off block
what you need to do first is to create an enter block that connects to your sink block
With that done, most of the blocks have a remove method associated, so you can do this, with any agent a:
a.currentBlock().remove(a);
enter.take(a);
Nevertheless, this is not good practice in my opinion, removing an agent from any block at any time will almost certainly mess up your flow logic in some way...
I am trying to implement reinforcement learning in Anylogic using pathmind library, the RL agent can take either of two actions which is changing the priority rule of a Queue block.
I have a Queue block where I'm using priority-based queueing. I have two priority rules: using agent's departure date & agent's wait time. I want to either of these rules during runtime using another function called doAction(action). A value 0 or 1 will be passed to this function. The function body would be like this:
doAction(action){
if(action==0){
//set departure_date as priority rule of Queueblock}
else{
//set wait_time as priority rule of Queueblock}
}
The expression of my queue block is given here. .
RL parameters are mentioned here.
What should be the code to set priority rule dynamically from the doAction(action) function?
I would suggest to rather make the priority rule dynamic inside the queue.
I assume you have some agent with a field for departureTime as well as for waitingTime.
Then you can do something like the following:
You simply have a different priority level for each agent if the priority option changes.
Here I am using boolean useDaprtureTime, but you can make it as complex as you need and even have a function in the "Agent Priority" field that returns the priority level.
Just remember that you need to call queue.sortAgents() if you change the rule since only the new agents that arrive are sorted, not the entire list of agents waiting in the queue since this will be too resource-intensive.
To use priorities, you specify an expression to determine the priority of the agent in the Queue's "Agent priority" or "Agent 1 is preferred to agent 2" property (depending what priority scheme you're using).
So have that expression be calling a function (defined within the agent type in question) which returns either the departure date or wait-time alternative.
Also, you didn't say whether this is a global setting --- i.e., use either departure or wait-time-based priorities for the whole run --- or could change dynamically; if you want the latter, you potentially need to call the sortAgents function of the Queue block (which might be inside a Service or Seize block, depending what you're doing) at the appropriate times (i.e., when your prioritisation scheme changes) to re-calculate all the priorities for agents currently waiting in the queue.
EDIT: I see from your other comment that you're trying to use reinforcement learning, presumably learning how to make a decision on how to prioritise the agents. (You should put that in an edit to your question since it's pretty important and relevant!)
So if you view the queue as the 'learning agent', you need to separate the learning action (which will set up / decide which prioritisation scheme you're using) from then using that scheme in the prioritisation.
This depends on whether you're using a Queue on its own (with priority based or agent comparison queueing), or you're doing this within a Service or Seize block. It matters because the on-enter action of the latter runs before the priority calculation expression but, with a plain Queue, it runs after the priority calculation.
Case 1: Using Service or Seize block
Have the on-enter action be the RL action which would then, say, set some variable to say which prioritisation scheme it had chosen and then call sortAgents on its embedded queue (self.queue) to recalc all the priorities. Then have switches in the priority calculation expression as above to do the calculation for the incoming agent using the required scheme.
Case 2: Using a plain Queue block
As above, but do the prioritisation scheme decision in the on-at-exit actions of all immediately preceding blocks (i.e., so that this is run just before the agent arrives at the Queue block and has its prioritisation allocated).
You can always use 2 queue blocks and send agents to only one using a SelectOutput block in front of them.
Each agent decides which queue to use based on your conditions.
By following your advice I’m constructing small models to learn how to use AnyLogic and build my simulation.
I need discrete events diagram interacting with agent based, where the agent based will represent a “service process” based in a previous recommendation it was straight forward to trigger the agent based activity, but I cannot stop or suspend or delay the “delay” block, I tryed to use the “until stopDelay is called” function but I could not make it work, I decided to test with and cyclic event inside the discrete event agent and but was not possible. I am considering that maybe my approach is not correct, and I need to use a different strategy to stop the discrete events process while the agent-based process is running, however since agent based is attempting to simulate some human behaviour, I’m interested in the time variations this could cause to the discrete events process. So my question is how to stop or suspend the “service delay or the delay blocks and restart them from the agent based diagram?
If you just need to store an entity somewhere until Agent process is done then I would recommend using using a 'wait' block instead of a 'delay'. The whole point of a delay is to have a timed exit so suspending it doesn't align with the intended use-case. You can read more about 'wait' block here.
I found the the Job Shop model example, some blocks using stopDelayForAll(), with a "if" code block, so I noticed that it was using a parameter, so I made some changes and the code I'm using and worked is this:
if ( Inqueue >= queCap )
delay.stopDelayForAll();
"Inqueue" is a variable capturing data from the delay block and queCap is a parameter telling the queue block capacity.
I'm a new AnyLogic user so hopefully this is a simple problem. I would like to use a block as to represent a storage area for items to be used in an assembly, I am using the delay block with delay time of 0, but maybe the queue block would be more appropriate? I have set up a model in which every X number of seconds a "truck" arrives and if the delay block contains less than a specified capacity of elements, the inject function is called to refill the block. This sort of works, but is seems that the agents are flowing through the delay block's out port and thus do not count toward its capacity (that makes sense to me...) resulting in my source blocks continuing to create agents when the system isn't ready for them. My delay block is followed by a "move by transporter" block which seems to be getting all of the delay blocks outputs immediately. There are only two transporters in my model and I am not sure why more than two agents can be accepted by the transporter block at a time. I set my transporter fleet to have a capacity of 2 but that did not solve the problem.
Any advice would be helpful! Perhaps a different approach is needed. My goal is to have an essentially unlimited pool of parts at the inlet of the factory, but only create agents when the downstream processes are able to pull them in. Thanks in advance!
Welcome to SOF :)
Best use a "Wait" block here:
Let your trucks dump stuff into "Wait" whenever they arrive. Your downstream block can now pull them when they are ready using myWaitBlock.free(someAgent for as many agents as they want to pull from it.
Similarly, you can use a Delay with infinite capacity and set its type to "Until stopDelay() is called". Then similarly as the "Wait" block, you call myDelayBlock.stopDelay(someAgent) when you want.
Another option: Use a hold-block in front of a normal (infinite) queue and unblock it when ready: myHoldBlock.unBlock(numToLetThrough) --> probably the easiest
PS: Please also check how to ask good questions here on SOF, yours is very long, much easier to understand with some screenshots :) --> https://stackoverflow.com/help/how-to-ask
If someone wants to delay an agent over the path, the delay block can be used customizing the delay time in order to get a deterministic exit time matching the desired simulation time.
Exists an alternative to that?
You can use a wait block with an event inside the agent that is going to be triggered after your delay time is over and call the free() function to get out of the wait block.
Nevertheless, you can customize your delay time in the delay block by using agent.delay (assuming that you have a variable called delay in your agent that identifies how long the delay will be for the agent)