I'm running some Simulink Simevents models. Every time I need to start from certain initial condition, such as certain number of entities in different queues and certain resource/server states. What I do currently is to let the model run for some time until the initial condition is researched, stop it, then test different parameters. Is there a way to save and rerun from certain initial condition, so every time I can run from the same state?
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I have a model as shown below with two situations, I am running it for two situations.
In the first run (for situation1), I write traceln function as "traceln(productDemand)" in the "event-generateDemand" placed in "Main". At the end of simulation, I get the values in the first column below.
2)In the second run (for situation2), for once I write traceln function as "traceln(main.productDemand)" in the "event" placed in "Producer" agent.At the end of the second simulation, I get the values in the second column below.
Normally, these two values are always same , it expected that at the every simulation time they have to be same, but they are not same as shown in the Fig.1. what's the problem? Why the "productDemand" variable is different when we try to access from another agent at the same time?
I hope I was able to explain my problem.
Fig.1- The obtained results as table format
Fig.2- The screenshot of Event placed in Main
Fig.3- The screenshot of Event placed in Producer agent
Fig.4- The obtained results for both traceln functions on the running
Fig.5- Simulation experiment screenshot.
fig.1
fig.2
fig.3
fig.4
fig.5
There is no bug in the model it is just a simple case of timing. Not all events occur at exactly the same "time" although they all occur at the same timestep. One will always execute before the other.
See the simple example below:
I have eventA that increases the variable value and then traces the value (similar to your event on main)
Then I have another event that traces the variable as well, similar to yours in the agent.
Yet when I run the model at the same time the variable appears to be different from the different locations of tracing
If you click on the Events tab in the console you will see that event B is scheduled to run before event A
Even though both will run at the same timestep in the model they don't run "at the same time"
If you want to be in total control of what happens on a specific time step, it is advised to have one event that runs at the time interval you want, e.g daily, and have it sit on main and then call all the functions in the order you want them executed.
If you don't do this then AnyLogic will schedule the events as they get created, which most of the time is the order in which you placed them on the canvas.
Good day
I'm a new user trying to find my with Anylogic.
Any help with the following question will be appreciated.
Is it possible to start a model with initial values/quantities given to certain blocks/sections in a model? In other words not have the model start from 0 but from the values given.
You can run a "warmup" period manually and save that as a model snapshot. In future runs, you can start off from that snapshot by loading it. See the help on model snapshots
This is the general problem of model initialisation (e.g., if you're modelling a manufacturing facility, you may want the run to start with the facility at the state it would be at on 9am next Monday morning). There is no generic answer: what initialisation you need is 100% model-dependent (as is how easy/hard this is).
In particular, process models make this difficult because entities (agents) are expected to have flowed through the process up to the point they 'start' in. You can use things like extra initialisation-only Source/Enter blocks to 'inject' agents into the appropriate process points, but in most models it's not this easy: you will have all kinds of model state that needs to be made consistent with this (e.g., the agents flowing through the process might have attributes which have changed based on what's happened to them so far, so this would have to be made consistent).
That's why warm-up periods (letting the model run 'from empty' for a period until its state is qualitatively what you want as your starting point) is a common approach. Model snapshots can help you here (see Ben's answer) but they're not the only way of doing it. (You can also just 'reset' all your metrics/output gathering at the point when you determine the warm-up period has ended --- i.e., you are effectively establishing a new 'time zero' --- but, again, exactly what you need to do is 100% model dependent.)
so my model works fine, but since I introduced conditional events (= an event that triggers once a specified condition is met), I find that the computational performance is decreased.
This is especially annoying when I run experiments with many iterations...
Is there an alternative way to trigger an event at a specified condition?
Thank you :)
The answer to this will be triggering events directly by the mechanism that are influencing the conditions you are monitoring. So instead of having the "permanent" condition check, make sure that each time the condition changes you are triggering a check. If that is not possible, because there are too many influencing factors, or it is continuosly changing, consider a cyclic check in discrete timesteps at an interval that suits you. Even this will be much more performant (depending on your choosen time check interval) then the current continous monitoring.
Example on how to do an event trigger monitoring instead of continous monitoring:
In your main, add global counter variable of type int (here: nrAgentsState1) and create a function to update that variable (here: updateStateCounter). Also in the function: a check that triggers a function whenever your threeshold is reached.
In your transition leading into the state you want to monitor (here: state1), call the function in main that updates the global counter. For the transition leading out of the monitored state, add the same action, but with a -1 as parameter.
I want to set the warm-up period in AnyLogic Personal Learning Edition. I searched for the warm-up period place in AnyLogic, but I couldn't find any thing about the warm-up period.
Is there a warm up period in Anylogic or something like this?
There is no default warm-up setting as it would not make sense given the vast flexibility of the tool and user needs.
It is easy, however, to set it up yourself. As usual, there are many different options, here is one:
create a variable v_WarmupDuration on Main, set it to whatever many time units you need
any data object you want to only record after the warmup period, ensure it only captures data if time() > v_WarmupDuration.
Events can have a custom initial time which you can use v_WarmupDuration for.
Functions that log data can only do so if time() > v_WarmupDuration, and so on.
Alternatively, log all your data as normal but add time stamps to them. Then, you can
Creating a warmup variable works fine for metrics you create yourself.
But if you want to use the built in functionality like histograms created from timeMeasureStart and timeMeasureEnd blocks in Anylogic, you will also need to add an extra select option so e.g. assuming you set v_WarmupDuration to 60 minutes, then you need a select block with a decision on false that goes straight to sink block or the next element after the timeMeasureEnd.
Condition if true: time(MINUTE) > v_warmupDuration
That way, the warmup period will not accumulate into the dataset of the timeMeasureEnd.
If you want to set this as a parmeter to an experiment, then ...
Add a variable to the experiment page off the screen e.g. v_warmupMins
Add a control like a slider on the experiment page and link to the variable v_warmupMins
Add a parameter to hold the warmup time in the Main canvas e.g. p_warmupMins
On the experiment properties, set the parameter p_warmupMins = v_warmupMins
to programmatically add this time onto the StopTime, add this to the Before Simulation Runs
getEngine().setStopTime( getEngine().getStopTime(MINUTE) + v_warmupMins );
Now when i run experiment with slider set to 60 mins, it adds 60 mins onto the stoptime and runs the experiment without accumulating metrics until that time has passed.
Hope that helps.
I'm building a model with AnyLogic using the Process Model Library (PML).
In my network I have 4 "source" elements that emits agents, they are all of the same type but with a different "category" string ID inside them (saved as a variable) to differentiate them; they are purchase order from different departments. I have also inserted blocks to measure the time the agents spend to exit from the assembler elements (you will see in the picture inside the red circles). This is the time that I will want to plot in a graph to show how fast they are.
After some test and reading the documentation I have see that when an agent pass under the start photocell (agent of any department) a timer is activated and the opposite when an agent (agent of any department) pass under the stop photocell the timer is stopped. Also in case of agent with different category IDs.
How can I synchronize the timers to measure time of object with the same category ID? I want that if the first source element "Category Nilo&Salmoni" produce an agent the stopWatch measure the time of this one and not of another one, emitted from another category, that reach the stopwatch first.