I am wondering how I can combine "while condition is true" and "given quantity" at the same time, regarding AnyLogic dropoff block.
The following chart is working well. While condition (agent.aclass == true) is true, element agent (Cargo) are dropped off. For your reference, Cargo has a bool parameter (aclass or !aclass) .
However, my problem is that "all available element agents are dropped off". I would like to specify a certain quantify (for example, 1, 2, or whatever) to be dropped off, keeping the condition "while condition is true".
Would you help me?
All agents are dropped off even though I want to specify the quantity to be dropped off.
Yes, the Dropoff block doesn't support what you want directly, since the dropoff 'protocol' can only be "All available" or "Specified number" or "While condition is true".
Easy solution
The easy way to get round it is to incorporate the 'have I dropped off beyond my threshold?' check into the condition.
So you would
Maintain a count (via an int Variable called, say, numDroppedOffThisBatch) of the number currently dropped off in the current 'batch', reset when the agent enters the Dropoff block ("On enter" action).
Change your Dropoff while condition to be agent.classA && (numDroppedOffThisBatch++ < 2) if, say, your threshold was 2.
That is, you only dropoff it it's a class A cargo and the number you have previously dropped off for this carrier agent is less than the threshold. The ++ after the variable name is a postfix operator in Java, which means it only increments the variable after it has been used in the expression. (So it does represent the number already dropped off.) You could equally have used ++numDroppedOffThisBatch <= 2 but the variable name is a bit misleading then.
Overly-complex but interesting alternative
Another option is as below, which effectively 'instantly re picks-up' (i.e., in zero sim time) the agents that shouldn't really have been dropped off. This is much more complex but is an interesting approach to understand (and similar things are useful in other contexts), so I've left it in...
It's tricky because you have to understand some under-the-covers details of the order in which things happen with a Dropoff block. Basically, dropped-off agents have their "On dropoff" actions run and are sent to their next block before the carrier agent leaves the Dropoff block. This actually makes things easier for us since we know we can 'initially process' dropped-off agents before the carrier agent leaves. So, we
Dropoff using the while condition as currently, but then have the dropping-off agent go into Pickup block (set to pickup "All available agents") and the dropped-off agents go into a Select Output block which goes either to a Queue (attached to the Pickup block via its special port) or its normal current destination (which looks like a MoveTo block from your (tiny!) screenshot).
Maintain a count (via an int Variable called, say, numDroppedOffThisBatch) of the number currently dropped off in the current 'batch', reset when the agent enters the Dropoff block ("On enter" action) and incremented as the dropped-off agents are dropped-off ("On dropoff" action) which is before they actually leave the block or test the following SelectOutput condition.
Also maintain another count variable numProcessedThisBatch (also reset to zero when the carrier agent enters the Dropoff block).
Agents dropped off then go into a SelectOutput which, if numProcessedThisBatch is greater than or equal to your 'how many should really have been dropped off' threshold, get routed to the Queue; otherwise they carry on as normal. (Note we are not checking numDroppedOffThisBatch here, which will always be the total number dropped off at this point.)
When a dropped-off agent enters the Queue or MoveTo blocks (i.e., when it finishes 'processing' either way), increment numProcessedThisBatch.
Below is a sample process flow screenshot (note the meaningful naming of blocks). The bit outside the red box is just stuff I added to setup a carrier agent with a mixture of class A and non-class-A Cargo agents via the buttons (and I just represented the 'follow on' flows for the carrier and should-actually-have-been-dropped-off cargo agents as nominal Delay blocks).
Here I had the carrier agent contain 3 class-A cargo agents and 2 non-class-A one, with a threshold of 2 agents to 'actually' dropoff (which I held in a variable for clarity).
To make the sequencing clearer (and to show how everything occurs at the same sim time), below are some traceln console messages produced which help understand what's happening. (The ones after I manually set up the carrier via the buttons are prefixed with the simulation time.)
Creating cargo class A agent
Creating cargo class A agent
Creating cargo class A agent
Creating cargo non-class-A agent
Creating cargo non-class-A agent
Creating carrier agent
6.699999999999991: carrier dropping off cargo agents by condition
6.699999999999991: cargo On dropoff action
6.699999999999991: cargo On dropoff action
6.699999999999991: cargo On dropoff action
6.699999999999991: Cargo agent starting normal process: class A true
6.699999999999991: Cargo agent starting normal process: class A true
6.699999999999991: Cargo agent ready for instant pickup: class A true
6.699999999999991: Carrier agent entering post-dropoff pickup
Notes:
It would also be a lot better to then encapsulate all this dropoff-by-condition-and-number logic into a custom block which you can then reuse wherever you want it (and avoid polluting the main process-containing agent with variables). That's obviously another level of detail and complexity.
This behaviour of the Dropoff block with a following SelectOutput is actually quite subtle. SelectOutput block conditions are evaluated before agents actually leave the previous block. (Because SelectOutputs are just routing decisions, they aren't really 'part' of the flow, in the sense that agents spend no time there; think of them as being used to say 'Where should I go next when I leave the preceding block?'.) That is why many blocks (like Delay) have "On exit" and "On at exit" actions. (The latter runs before AnyLogic even tries to see what block it should go to next, so will happen before a following SelectOutput check.) It just happens that Dropoff blocks run their "On dropoff" actions before checking what the onward block might be; thus they function in the same way as "On at exit" actions in other blocks.
Related
In my model I am transporting (path guided) several types of products (motors) by an agv trough a manufacturing line with 27 cycles. It´s a flowing manufacturing line. That means the product gets manufactured while the agv is constantly running.
To model that I created an agent population called "motors" with parameter "axelType" (string) which is loaded from column "axel_type" in database "manufacturing_sequence" (local excelsheet) and is placed on Main.
Each motor is placed on an transporter "agvAssembly" (in Flowchart as: Transporter) and runs from node "locationCycle1" all the way to "locationCycle27".
Now I want to change the transporters speed at each of the 27 cycle nodes dependent on the currently loaded motor. To do that I got another database called "speeds_axel" which includes all the needed speeds for the cycles and respective parameter name for axelType (column axel_type).
So now, when the transporter enters a node I have to check first the nodes name. Than I want to read out the parameter "axelType" of the currently in that node entered agent "Motor" and search in the database for the respective speed.
In the block "transporter Fleet" - "On enter node:" I wrote as an example for cycle 1 the following:
if (node == locationCycle1) {
unit.setMaximumSpeed(
selectFrom(speeds_axel)
.where(speeds_axel.axel_type.eq(motor.axelType))
.firstResult(false, speeds_axel.cycle1)/60.0,MPS);
}
When running the model I get the following error:
"motor cannot be resolved to a variable"
(location: TransporterFleet)
I think that error accures because my approach doesn't specify which motor I mean. How can I clarify to AnyLogic that I always mean the current motor which enters the node?
I need something like this:
if (node == locationCycle1) {
unit.setMaximumSpeed(
selectFrom(speeds_axel)
.where(speeds_axel.axel_type.eq("get motor which is currently in locationCycle1".axelType))
.firstResult(false, speeds_axel.cycle1)/60.0,MPS);
}
the biggest problem in your model is that you don't follow conventions. An agent type should be named with an uppercase first letter
Why is this important? Because you want to make the difference between Motor, motor, and motors
Motor is the class (or Agent Type)
motor is an instance of that class (or agent type)
motors is a population.
Since you don't follow this convention, you make mistakes of this kind since motor is a class
in your case when you do motor.cycle1
if you followed the conventions, you would be doing
Motor.cycle1 (which is obvioulsy wrong)
Note that Motor is the Agent Type name, and what you really want is to know for a particular motor what the value of cycle1 is
The first thing you need to do with this model, is get back to using the conventions, and this will probably solve this problem and many problems in the future.
Just because you have a population called motors (which the agents within your flow 'come from' --- though it looks like they don't actually; see later), this does not mean that you can 'magically' refer to the current agent via the singular form motor at any point in the code. (And, similarly, your agent type being Motor does not mean you can use the lower-case form to refer to 'the current one'.)
In Transporter Fleet block "On enter node" actions, you refer to the current transporter via the unit keyword; see the help page. The motor is not the transporter; it's the thing being transported.
So, just use the "On exit" (or, better, "On at exit") actions of your MoveByTransporter blocks (which trigger on arrival at the destination node), where you can refer to the current motor (the agent in the flow) via the agent keyword; again, see the block help.
But, from a quick glance, there appear to be a few important changes/simplifications you should also make (though hard to definitively tell without details of all your code):
You are using a Source block to add agents (motors) to the flow when you have already created the motors in your population. You should be using an Enter block instead to add the (already-existing) Motor agents to the flow at the appropriate time (triggered by code: I imagine you want one to start at model start time, requiring code in Main's "On startup" action, and then others added either at certain simulation times or when earlier motors reach a certain stage in the process...). If your population was actually just for 'templates' of data for each motor axle type (and you would then potentially create multiple instances of motors for a given axle type) then your current logic might make sense, but your screenshot of your manufacturing_sequence table makes clear that isn't the case. (If you did go that route, you would want to rename your population so that its purpose was clear.)
It looks like you have a 'looping' process (with the same process behaviour for all your in-sequence nodes), so you should look to make your process generic with an explicit loop (so you don't have near-copies of blocks for every node in your sequence). There is a fair amount of detail in terms of how you do this but roughly:
Track the node the motor is currently in (or its sequence number) via a variable in the Motor agent.
Use a collection (List) which contains the nodes-in-order to determine where it has to go to next.
Your process would have a MoveByTransporter --> Delay --> SelectOutput sequence (plus TimeMeasureStart/End if you're using them), where SelectOutput loops back to the MoveByTransporter if the motor is not yet at the last node.
I am trying to stopDelay at delayNucSafe1 (See Screenshot) when the car exits at carMovetoScale1 They way I am currently doing it is at the "On Exit" block of carMovetoScale1 typing: delayNucSafe1 .stopDelay() but I am getting an error that says:
Description: The method stopDelay(Agent) in the type Delay is not applicable for the arguments (). Location: Scale House/Main/carMoveToScale1 - CarMoveTo
Logic Flowchar
where I am asking to stopDelay
Can someone help with this?
The stopDelay(Agent) method is for use when there are multiple agents waiting within the delay and you need to stop the delay for ONE specific agent. If this is the case for you, you would need to know which agent you want to stop the delay for.
For instance, you would call: delayNucSafe1.stopDelay(delayNucSafe1.get(0)) to stop the delay for the agent at index 0 in delayNucSafe1. (This code would also work if there is only 1 agent in the delay).
On the other hand, if you know for sure that there will only ever be 1 agent in the delay (or if you'd like to stop the delay for every agent simultaneously), you would use the method: stopDelayForAll(). This method has the benefit that it doesn't need an argument, but it will obviously cause problems if there are multiple agents waiting in the delay, each of which need to be released independently.
So in summary:
delayNucSafe1.stopDelay(delayNucSafe1.get(agentIndex))
will stop the delay for the agent at index agentIndex within delayNucSafe1. And:
delayNucSafe1.stopDelayForAll()
requires no arguments, and will stop the delay for all agents within delayNucSafe1
Anylogic: This should be simple but I just cannot find it in the help files..
On creating a new agent instance, we know there are four parameters and what they are, but not in what order they were defined. Lets say parameters are "type_of_car" (String), "number_of_pax" (Integer), "automatic" (boolean), "fuel_capacity" (double). Now when calling: new myagenttype("ford", 5, false, 55) the agent gets created as a ford with 55 pax, manual and 5 liter fuel capacity - which is all wrong. (it seems the definition order of the parameters in the agent definition are in a different order)
How do we include the parameter name (or definition) when we call new agenttype() to avoid this problem, ensuring the right value gets assigned to the right parameter?
The problem originates because of a bug in Anylogic's logic in triggering functions. We have a Split which creates a new agent and assigns the agent properties on the "On exit copy" - event, however what Anylogic does is it creates the agent, forward it to the next logical block (a decision node), then execute the code of the decision - all wrong now for the agent's properties are undefined - and only then executes the "On exit copy" event which assigns the agent's properties. Very frustrating.
This is actually not a bug, this is defined in the simulation experiment properties, in the randomness section, with the "selection mode for simultaneous events" property. The default is LIFO, but if you want the opposite behavior in your case you should use FIFO... I always use LIFO too, and in these cases, sometimes I might use a 1milisecond auxiliary delay between the split and the next block in order to control the order manually... if you do that, you will solver your problem in fact... just use a 0.001 miliseconds delay after your split
Now from your Agent Type problem, the arguments for your class constructor should be written in order, and the only way to know the correct order is by using the autocomplete feature when you write new agenttype()... the autocomplete will tell you the order in which you should write your constructor arguments.
I have an airlock (small room called AL_2216) between 2 areas. The airlock has many different agent types passing through it (cart, product, operator, etc). There are queuing areas on either side of the airlock.
Because the space is small, I built a short flowchart that has a queue and restricted area blocks that all agents must pass through when going through this space. If the restricted area's capacity is full, the agents wait in either the InsideQueueArea or OutsideQueueArea depending on the direction they're going.
I send agents via Exit and Enter blocks to this flowchart and it works great on the top portion of the flowchart.
BUT if I try to use an Enter or Exit block in the prepare flowchart, I get this error:
I tried using a custom block instead of Enter and Exit blocks, but that creates a new instance of the code each time and the restrictions don't work together across the multiple custom blocks.
This airlock is just one of many in my model. Without referring to the same code, I'll have multiple copies that need to refer to each other's restricted areas and the flowcharts become huge and complicated. Is there a way to get around this?
EDIT:
I'm not sure what to do with these ports. They have no properties that do anything:
EDIT2:
Here's a file to see the behavior - Model2.zip
The Prepared flowchart portion is set to "ignore" so the code will run. You can see the operators and the carts passing through AL_2216 with only 2 being allowed at a time. If you uncheck "ignore" for the prepare flowchart, the error will trigger.
AnyLogic sent the right answer!!
So I was asking Anylogic a different question and they recognized my name from this post! They sent a fix to me and it works exactly the way it should! The exception error message I was getting "out: 0 isn't supported for..." made me think the exit/enter blocks were not supported in perparation flowcharts.
But actually, the seizeCart block didn't know where to start the prep flowchart because it wasn't directly connected to the resource task start block. A quick setting change under the Advanced section of the seizeCart block defining which resource task start block to start at did the trick! Here's the email from AnyLogic:
-The error text and documentation are not sufficient for understanding this (the error text is confusing), I suppose it is obsolete error text. We will rectify the description;
-Under the question there is a more generic discussion which seems to be unrelated to the initial problem. Please let me know if I miss something or if your model does not work as you expect even after adjustment of seizeCart block property.
I think you should replace the Enter and Exit blocks that lead to the bottom input of your seizeCart Seize block with simple Port objects (from the Agent palette).
As per the help for Seize:
So it wants a direct link to a ResourceTaskStart flow and your Enter/Exit combinations might be ... not "direct" enough... Try it.
So here's what I ended up doing. It's the best I could come up with that could be easily replicated for lots of airlocks.
I've added a wait block (dummyThruAL_2216) to my Product flowchart prior to seizing the cart. This wait block injects a new Agent into sourceDummy at the cartHome node. The dummy then seizes a cart and moves through the airlock and it's restriction. Upon exiting the restriction, I check what type of agent and direct the agent to the correct exit block. The dummy agent and cart move to the Product where the dummy agent releases the cart and sinks. The sink frees the wait block and the Product seizes the cart that is right next to it and continues on it's journey.
It's an easy copy/paste to add more airlocks. Not as nice as my original, but what are you going to do... Thanks for everyone's help and suggestions.
As others have said, there are (not really documented) restrictions on what blocks you can use in preparation and wrap-up flowcharts, which mean what you're attempting won't work.
As you say, it's important to keep a single 'instance' of the airlock flow so that the restrictions (queue and restricted area) are 'global' when this represents the same physical airlock. (Otherwise a repeated custom block is precisely what you should use for each different physical airlock.)
Your best option (and assuming you needed to attach the Cart resource to the Product) is probably to
Add dummy agents (via Source block inject calls) to a separate mini-process that represents your resource preparation requirement (but now not attached to the Seize block).
Replace the Seize in your main process with a Seize-Wait-Release-Seize combination:
The Seize block seizes the cart as normal (without moving or attaching it; no 'Send seized resources' or 'Attach seized resources' options) and then injects an agent into your mini-process (which can use Exit and Enter blocks to use the airlock sub-process). This agent represents the seized resource agent (Cart) and thus should start where it starts and be animated so it looks like it. (You can make the actual Cart temporarily non-visible during this mini-process.)
When the agent reaches the end of the mini-process (at a Sink block), instantly move the related Cart to your node (use jumpTo), make it visible again and free the Product agent from the Wait block
Release the seized Cart and then immediately re-Seize it, but now attaching it (so the animation looks correct). If you use the Resource selection 'Nearest to the agent' option you should be guaranteed to seize the correct cart. (You can also use the 'Customise resource choice' option with some code to ensure that you absolutely always choose the same Cart.)
(It is simpler than the above if you don't care about having a correct animation, and you can use custom blocks to make this block combination reusable and thus not too clunky.)
Edit: A very similar alternative which also works (and is the basis for your own answer) is to have a dummy agent representing your Product in the sub-flow which seizes (and attaches) the actual Cart agent, leaving it at the Product's location to be immediately seized as above. This is slightly better since you don't have to worry about the visibility and 'jumping' of the real resource agent, plus you can move a Seize and a Release from the main flow (which now just has Wait-Seize) to the sub-flow (thus 'hiding them away').
I'm simulating a security control process, and i can't do that each passenger pickup their baggage. I have tried with Match, Combine, Pickup, but I still can't execute the commands correctly.
I've created the follow flowchart, and the problem is in the wReclaimPax, pickup and wReclaimBags blocks (you can see them in the picture).
https://ibb.co/v3V57Tm
I saw this link Anylogic - Combined multiple items back to original owner to understand something, but I still need help.
I've created 3 functions:
isMatch:
if(equipaje.pasajeroLink.equals(pasajero.equipajeLink)){
return true;
}
return false;
paxBags:
for(int i=0;i<wait.size();i++){
Pasajero p=(Pasajero)wait.get(i);
if(isMatch(p,bag))
return p;
}
return null;
bagsPax:
for(int i=0;i<wait.size();i++){
Equipaje e=(Equipaje)wait.get(i);
if(isMatch(pasajero,e))
return e;
}
return null;
Assumed context
You haven't really explained how your code is related to your process but I'm assuming the following:
Because this is luggage-retrieval, you want to ensure that a passenger
agent (Pasajero) only enters the Pickup block (representing taking bag from
carousel) when his bag (Equipaje agent by the look of it) has
arrived into the wReclaimBag Wait, and been released from it to
queue4 Queue.
For this you need triggers (to remove agents from Wait blocks) when
either a passenger (Pasajero) arrives in wReclaimPax Wait, or a bag (Equipaje) arrives
in the wReclaimBag Wait (because you don't know whether the passenger or their bag will get to their respective Wait blocks first).
So your paxBags function is called in on-entry action of the wReclaimBag Wait, and your bagsPax function in the on-entry action of the wReclaimPax Wait.
Possible problems with current approach
Without knowing more of your model it's hard to say but problems I can think of based on what you've supplied are:
Your functions return the Pasajero or Equipaje if there is one that matches. Your match check relies seemingly on bidirectional connections (links) between Pasajero and Equipaje. Obviously if they're not setup properly the model won't work and, if you're using bidirectional connections you shouldn't need to check both ends.
Your functions need calling so that, if they return non null, they then free the matching agent from the other Wait block, and free themselves. Are you doing that? Without checking, there may be issues with calling free for yourself as you enter a Wait block (since this kind of depends on AnyLogic internals as to whether you count as being 'in' the block at this stage and can be freed). If this seems to be the problem you could create a timeout 0 dynamic event instance to do the free so that you're not doing it within the scope of the on-enter action.
Your pickup block (since it's been setup so that the entering agent will always want to pickup the first agent (Equipaje) in queue4) just needs to be set as waiting for quantity 1 (though see below).
If you've done all this the most likely problem is that the underlying events ordering of AnyLogic is affecting things. When you free agents I'm fairly sure the freeing actually happens in a timeout 0 event scheduled under-the-covers. So it may be that the passenger arrives at the Pickup before their Equipment arrives in queue4 though, if you set the Pickup to be "Exact quantity (wait for)", with quantity of 1, it should handle that.
The animation of the process (numbers in/out/within each block and details when clicking on blocks) should also help you debug what is going wrong; e.g., are bags being left in the Wait when they should have been released, etc.
P.S. With this kind of thing you should always create a minimal example model to make testing the issue/solution easier (and for sharing in help forums such as this where the rest of the complexity of your model is irrelevant). Often you find the problem 'naturally' in the process of trying to construct such a model that reproduces your problem in a minimal way.