I am using parameter variation in AnyLogic (in a system dynamics model). I am interested in how one parameter changes with the various iterations. The parameter is binary: 0 when supply of water is greater than demand and 1 when supply is lower than demand. The parameters being varied are a given percentage of decrease in outdoor irrigation, a given percentage of decrease in indoor water-use, and a given percentage of households that have rainwater harvesting systems. Visually, I need a time plot where on the x-axis is time (10,950 days; i.e. 30 years) and the binary on the y-axis. This should essentially show which iteration pushes a 1 further into the future.
I have watched videos and seen how histograms and 2D data are used to visualize the results of the iterations, but this does not show which iteration produced which output specifically. Is there a way to first, visually show the output as I have described above and second, return the data for a specific iteration?
Many thanks!
Parameter variation experiments have After Iteration and After Simulation run actions that are executed after each iteration and simulation respectively. Here, it is possible to access the values inside the simulation object after it finished but before it is destroyed. There is also a getCurrentIteration() method which can be used to control the parameter variation experiment and retrieve the data.
For more detail please consult here and see "SIR Agent Based Calibration" example model in AnyLogic example models library (Help -> Example Models).
Related
Im currently building a Anylogic model and want to calculate average time spent by customer in different flow paths (I have added the process flow below). In the picture i have named the paths i want to calculate the average time as path A and path B
Anyligic has dedicated blocks for this (although it can be done simply in code).
See in detail here.
The TimeMeasureEnd block contains a dataset.
The following code returns the average of the Y-axis values:
timeMeasureEnd.dataset.getYMean();
Good luck!
Using system dynamics on anylogic how can you model a simulation that will give an infectious curve of this nature(Below picture) using SEIR.
enter image description here
I have tried to simulate, however my graph goes up and down. It does not oscillate as per the attached picture.
I need to simulate something similar to the graph for my assingment.
There should be three types of events in your model.
First, lets call it "initial spread", is triggered on the start of your simulation.
Second, lets call it "winter season", is triggered annualy in November\December.
Third, lets call it "mass vaccination" - you can decide when to trigger it and for what selection of your agents.
So first two are kind of global events, and the third event is specific to some sub-population (this can make the third wave kind of "toothy" if you trigger it in slightly different moments for different populations).
That is pretty it.
Curios to see how your model will predict the fourth wave - second winter season of your simulation. So keep us updated :)
There are a number of ways to model this. One of the simplest ways is to simply use a time aspect for one of your infection rate parameters so that the infection rate increases or decreases with time.
See the example below.
I took the SIR model from the Cloud https://cloud.anylogic.com/model/d465d1f5-f1fc-464f-857a-d5517edc2355?mode=SETTINGS
And simply added an event to change the Infectivity rate using an event.
Changing the chart to only show infected people the result now looked something like this.
(See the 3 waves that were created)
You will obviously use a parameters optimization experiment to get the parameter settings as close to reality as possible
I am new to this and lost about how to create visualization for the AnyLogic sensitivity analysis. Here is the summary:
I have dataset that captures dependent and independent variables at the end of simulation run (just captures one pair at the end). Trying to vary independent variable to see the impact on dependent variable. The resulting dataset is correct (when I copy and paste in Excel) but the chart looks blank.
Also, output states that it completed 5 iterations but I specified 10 and the data shows that there were in fact 10 iterations.
There are no parameters for the chart data (see the screenshot) but I am guessing it is automatically populated at the end simulation based on the code (also copied below)? Otherwise, I cannot figure out what goes into the chart data (tried to manually enter variables/datasets to no avail).
This is the code after each simulation runs:
Color color = lerpColor( (getCurrentIteration() - 1) / (double) (getMaximumIterations() - 1), blue, red );
chart0.addDataSet( root.died_friend, format( root.SocFriendBrave ), color, true, `Chart.INTERPOLATION_LINEAR, 1, Chart.POINT_NONE );`
I realize this is a very basic question but I am lost and cannot get on the right path based on the help I found. thank you.
Let's say you have 2 experiments: simulation (normal one) and sensitivity analysis (new one)
The only way for the chart to look blank is if your dataset died_friend is empty. This can happen for many reasons, but the reason I suspect it happens here, is because you fill this dataset with information at the end of the simulation run, which means that you are probably using the java actions of the simulation experiment.
The sensitivity experiment DOES NOT read what you write on the java actions of the simulation experiment, so that might be the problem.
If this is not the case, you need to check other possible reasons on why your dataset is empty when you run the sensitivity analysis.
Remember: the fact that your dataset has data in your simulation experiment, does not necessarily mean the dataset will not be empty on the sensitivity experiment.
Since the Sensitivity Analysis experiment is set up via the wizard, it would be better if you showed us how you'd set that up, rather than the resultant AnyLogic-generated code.
From what you've said here, it looks like you may be incorrectly trying to use datasets instead of scalar values. If there's one 'dependent variable' (model output of interest) then the 'independent variable' needs to be a model parameter (parameter of your top-level agent, normally Main, which the experiment will be varying).
So you should specify:
Varying the relevant parameter (looks like you wanted it to be 0, 0.25, 0.5, 0.75, 1 so min 0, max 1 with step size of 0.25)
Producing a chart for the scalar output you want. (If this was, say, a variable called outputValue, you'd use expression root.outputValue when setting up the chart in the wizard.)
Also you should only be getting more than 5 iterations if you set up your parameter variation criteria incorrectly.
(Dataset outputs in the experiment's charts are typically for where your model produces a time series as an output --- i.e., a dataset of sim time vs. value --- and you want the Sensitivity Analysis experiment to show charts with each run's time series as separate lines (i.e., time on the X-axis). Scalar charts are for where the X-axis is the varying parameter and the Y-axis the output of interest.)
I run a parameter variation experiment in Anylogic and collect histogram data about the number of specific agents. This histogram returns the min, mean, and max-value (among others).
I am looking for a way to get the dataset for one specific iteration only (the iteration that is closest to the mean-value of the histogram data).
Is there a way to return data for one specific iteration?
Many thanks!
Yes, but not with HistogramData objects.
Use normal Dataset objects in your experiment. In the properties, you can switch to "use x value as iteration" and store any value from your model iterations in the y-value.
Now you have a nice table with data from your individual iterations.
cheers
I am having trouble with the coding process or steps to extract data from the main and onto the parameter variation experiment in anylogic. I am currently working on total evacuation time due to random fire obstruction.
For now I have successfully obtained the total max evacuation time for 100 runs in my study but I also need another set of data for the number of exits obstructed during each run. My main has the collection (of 3 exits) availableExits and I can see what is obstructed during the simulation.
Furthermore, I would like to obtain data for the number of people evacuating at a particular time (for example number of pedestrians using exit at 120 seconds). I can see this in main from timeMeasureEnd and creating a histogram distribution graph, which shows number of pedestrians escaping at each time. I've managed to create one in parameter variation but when I run the experiment, I am unable to store or view the data as it keeps changing after every run.
Here is the code from analysis Histogram Data which is entered in after simulation run
data = root.timeMeasureEnd.distribution;
i would recommend to add a dataset to your main which would store all the values you want to keep in parameter variation. Dataset differs from histogram data in a way that it doesnt aggregate, it is just a raw array of values, and later you will not have a problem of "aggregating aggregated data".
So, after each simulation run you can access your dataset in main via "root" reference (as you are already doing it) and loop through it to store all the values one by one.