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Constants aren't supposed to change over time. My suggestion is to read the constants into an array, where the subscript serves as a virtual time axis. Then read from that array with VECTOR LOOKUP to get the time dimension.

I would be inclined to solve the system simultaneously. Often FIND ZERO is a better option than SIMULTANEOUS for this. Would have to see the equations to say more.

After further thought, I think the right way to do this is:

- Create a subscript for the hourly instances, like i : (i1-i8760)
- Read the data as constants into a subscripted variable, like
temperature = GET XLS CONSTANT( ... )
- Use VECTOR LOOKUP to read from that table, with x=Time modulo 8760.

You might take a look at how it's done in VenPy:
https://github.com/VensimSoftware/venpy ... py.py#L406

Hybrid models are really the target of Ventity. The ideal use case is a model that mixes aggregate SD, and maybe a moderate number of agents with complex dynamics. Ventity is not designed for situations with millions of very simple agents. This series considers infection models from aggregate, cohor...

https://ventity.biz/introduction-to-ventity-workshop/

This workshop used an ABM example.

I use "fraction" if it's a share (0-1) and "percent" if it's really %, 0-100. I usually define a constant, like "hundred percent = 100 ~ percent" for converting between the two.

I would expect GET DATA AT TIME to have extremely slow performance - most of the GET DATA functions cause a noticeable slowdown, unless they are wrapped in an INITIAL (which wouldn't work here). If the model is small this may not be a problem.

There's no built-in way to do this, but I can think of some kluges, though they might not be very efficient. How many variables are in this dataset, and what is the purpose of the repetition? Knowing more might make it easier to choose a solution.

This experiment does suggest another interesting case: if all the likelihoods and/or priors have a beta distribution with small a,b then all the density should be concentrated at the extremes of the range (or worse, the corners of the hypercube if it's multidimensional). In theory the algorithm can ...

I modified the hard bounds constraint behavior so the concentration of mass at the bound no longer happens, at least in a case like this with a uniform likelihood and (implicitly) flat prior over a unit hypercube. It probably still makes sense to apply some kind of prior within the range. We plan to...

Wish I'd thought of that sooner!

You might be running the nonparallel version of DSS. The installer currently installs both. You want to see DSS 10.x.x (MC) in your title bar or About window. If you don't see the option in the GUI, it won't work from the .voc - the options will behave like the normal nonparallel restart options.

A possible cause is that "activate on variable selection" is turned on for one of your analysis tools. activate var select.PNG You can right-click the tools to check and turn it off if needed, or use Tools>Analysis Toolset>New to reload a fresh toolset (losing previous unsaved settings).

vensim at vensim dot com.

I think the key question is, what tool are you using when you click on things?

Also would need to know operating system and Vensim version to say more.

Ventity also does data.

It starts with PLE+, though if you want to do much with the data (e.g., calibration optimization) you really want Pro or DSS.
https://vensim.com/comparison-chart-for ... gurations/

For visual comparison, I think there is one option: the Reference Mode tool. However, if you want your data to drive the model behavior, the lookup is it.

We'll look into it. In the meantime, if you have any detail about the circumstances, you can shoot us an email at vensim at vensim.com - if they arrive roughly concurrently, we'll know what's what.

Ah ... try this ...

However, this is an area of active development, using the shortest independent loop set methodology originated by Kampmann and developed by a number of others in the SD literature.

Also, when the input becomes nonzero, should there be an immediate pulse, or should the pulses be restricted to a particular time (for example, always in month 6 of the year)?

Is the input going to go from 0 to nonzero in a single step, or vary on/off over time?