Search found 3811 matches
- Tue Oct 03, 2023 4:38 pm
- Forum: Vensim
- Topic: best way to build a server for clients via the internet
- Replies: 14
- Views: 1010
Re: best way to build a server for clients via the internet
The fee part is a good argument for Forio. They have the architecture for paid use of models; creating that yourself is probably a substantial bit of work.
- Tue Sep 26, 2023 7:31 pm
- Forum: Vensim
- Topic: Reference modes in Vensim PLE
- Replies: 3
- Views: 468
Re: Reference modes in Vensim PLE
I can replicate this - it's a bug.
- Thu Sep 21, 2023 4:44 pm
- Forum: Vensim
- Topic: How to set up DSS to compile to C
- Replies: 1
- Views: 289
Re: How to set up DSS to compile to C
The section you want is in the docs, https://www.vensim.com/documentation/25945.html, but I see it's out of date. Generally what you need (assuming Windows) is: Edit C:\Users\Public\Vensim\vengine\comp\MDLDP64.BAT (this is the compilation script) Early on, you'll see a series of blocks that set up t...
- Fri Sep 15, 2023 3:52 pm
- Forum: Vensim
- Topic: Random with Log Normal distribution
- Replies: 2
- Views: 332
Re: Random with Log Normal distribution
Yes! I usually do something like the following: var = GeometricMean * EXP( GeometricSD*RANDOM NORMAL(-6,6,0,1,0) ) The GeometricMean has the same units as your target variable. The GeometricSD is the standard deviation as a fraction of the mean, i.e. the standard deviation of LN(var/GeometricMean) a...
- Wed Sep 13, 2023 7:17 pm
- Forum: Vensim
- Topic: Checking for NA input data with subscripts
- Replies: 4
- Views: 473
Re: Checking for NA input data with subscripts
I think your instincts were good here. Leaving the data in .vdf format should normally work. It's possible that there was a leak in 6.3 that allowed the NAN values to get into the vdf in the first place. For doing a round-trip vdf/vdfx conversion, .dat format is often the easiest, because it doesn't...
- Tue Sep 12, 2023 7:54 pm
- Forum: Vensim
- Topic: Checking for NA input data with subscripts
- Replies: 4
- Views: 473
Re: Checking for NA input data with subscripts
If you want to check for :NA: in a data variable, you need to use the :RAW: interpolation method. :INTERPOLATE: only returns :NA: if the series has no data at all.
- Mon Sep 04, 2023 2:50 pm
- Forum: Vensim
- Topic: Sensitivity analysis using the file option in a subscripted model
- Replies: 13
- Views: 774
- Mon Sep 04, 2023 2:49 pm
- Forum: Vensim
- Topic: Sensitivity analysis using the file option in a subscripted model
- Replies: 13
- Views: 774
Re: Sensitivity analysis using the file option in a subscripted model
When I save this as tab-delimited text, Excel quotes the column headers like "fracDWI[Male,Age15]" This is a nonstandard behavior, because quotes are not needed when the delimiter is tab (only csv). Unfortunately this is not legitimate quoting in Vensim (the subscript brackets should not b...
- Fri Aug 25, 2023 2:50 pm
- Forum: Vensim
- Topic: unit consistency bug
- Replies: 5
- Views: 1919
Re: unit consistency bug
Thanks Tom I also did not notice the mile per trip is constant, but still interesting how can this happen if there is a link between two variables. It should automatically make constant become AUX. I'm not sure we should do this, because the extra arrow could be a mistake. In the language, constant...
- Fri Aug 25, 2023 2:47 pm
- Forum: Vensim
- Topic: Error in a counter variable
- Replies: 6
- Views: 618
Re: Error in a counter variable
Here are some options.
I think one unit error might have been a typo in "dmnl".
I think one unit error might have been a typo in "dmnl".
- Fri Aug 25, 2023 2:25 pm
- Forum: Vensim
- Topic: Download link not working on any browser
- Replies: 7
- Views: 533
Re: Download link not working on any browser
Antivirus?
- Fri Aug 25, 2023 2:24 pm
- Forum: Vensim
- Topic: Sensitivity analysis using the file option in a subscripted model
- Replies: 13
- Views: 774
Re: Sensitivity analysis using the file option in a subscripted model
What error are you seeing?
I'm guessing that you're putting varname[range] in the headers. I don't think that works - you need to provide a separate column for each varname[element].
I'm guessing that you're putting varname[range] in the headers. I don't think that works - you need to provide a separate column for each varname[element].
- Thu Aug 17, 2023 5:46 pm
- Forum: Ventity
- Topic: Entity activation time
- Replies: 5
- Views: 1908
Re: Entity activation time
We can get you a nightly build when the fix is included.Just walked through with the debugger.
The first try fails due to loading sequence and issues the error message too soon. The automatic retry works. The bug is that the error message is wrong -- there is not a real problem.
- Thu Aug 17, 2023 4:12 pm
- Forum: Vensim
- Topic: unit consistency bug
- Replies: 5
- Views: 1919
Re: unit consistency bug
Actually, the problem with "miles per trip" is that the equation is constant, but the diagram includes a link from "attractiveness of driving" so the equation is invalid (inconsistent with diagram). We should probably upgrade the warnings to distinguish missing equations from mis...
- Thu Aug 17, 2023 4:05 pm
- Forum: Vensim
- Topic: unit consistency bug
- Replies: 5
- Views: 1919
Re: unit consistency bug
The others are either correct warnings, or Vensim cannot check as there is no equation to check against. Not so. "miles per trip" is a constant =20 and has unit mile/trip, but it's still reported as an error (no units). I suspect that the parsed model is so incomplete that Vensim fails to...
- Wed Aug 16, 2023 1:56 pm
- Forum: Ventity
- Topic: any plans for a Mac version of Ventity?
- Replies: 3
- Views: 2032
Re: any plans for a Mac version of Ventity?
[ ] Almost done.
[ ] In the works.
[ X ] We're thinking about it
[ ] It's complicated.
[ ] No way, don't hold your breath
"Don't hold your breath" might still be good advice.
[ ] In the works.
[ X ] We're thinking about it
[ ] It's complicated.
[ ] No way, don't hold your breath
"Don't hold your breath" might still be good advice.
- Wed Aug 16, 2023 1:55 pm
- Forum: Ventity
- Topic: any plans for a Mac version of Ventity?
- Replies: 3
- Views: 2032
Re: any plans for a Mac version of Ventity?
[ ] Almost done.
[ ] In the works.
[ X ] We're thinking about it
[ ] It's complicated.
[ ] No way, don't hold your breath
"Don't hold your breath" might still be good advice.
[ ] In the works.
[ X ] We're thinking about it
[ ] It's complicated.
[ ] No way, don't hold your breath
"Don't hold your breath" might still be good advice.
- Wed Aug 16, 2023 12:18 am
- Forum: Ventity
- Topic: Entity activation time
- Replies: 5
- Views: 1908
Re: Entity activation time
The HG B/D mixup looks like a bug to me. Checking with the devs.
However, it's not clear to me that compound keys are needed here, at least for S1. Every S1 Factory is unique, so the group isn't needed to find the factory.
However, it's not clear to me that compound keys are needed here, at least for S1. Every S1 Factory is unique, so the group isn't needed to find the factory.
- Wed Aug 16, 2023 12:08 am
- Forum: Ventity
- Topic: Entity activation time
- Replies: 5
- Views: 1908
Re: Entity activation time
I'll take a look.
- Mon Aug 14, 2023 5:11 pm
- Forum: Vensim
- Topic: Help with a sigmoidal behaviour in a stock variable
- Replies: 3
- Views: 583
Re: Help with a sigmoidal behaviour in a stock variable
Sounds like what you want is a logistic growth model. The model here https://vensim.com/vensim-video-library/#Introduction_to_System_Dynamics_With_Vensim has a variant of that near the 1hr mark, particularly if you make the product lifetime very long so that there's effectively no outflow from custo...
- Tue Aug 08, 2023 9:57 pm
- Forum: Vensim
- Topic: Units Check whack-a-mole
- Replies: 9
- Views: 1151
Re: Units Check whack-a-mole
Ventity licensing will be changing to look more like Vensim. In the meantime, we'll include a license with a Pub Rsch Vensim Pro license (email us at info at ventity.biz if it doesn't happen automatically).
- Mon Jul 31, 2023 7:19 pm
- Forum: Vensim
- Topic: how do I reload an existing dataset, including variable values?
- Replies: 5
- Views: 563
- Mon Jul 31, 2023 6:14 pm
- Forum: Vensim
- Topic: how do I reload an existing dataset, including variable values?
- Replies: 5
- Views: 563
Re: how do I reload an existing dataset, including variable values?
If you change variable values interactively, e.g. by moving sliders, the model always retains the underlying equation values as a default. If you change the equations, you have to manually change back. More advanced versions of Vensim can save and load change files (.cin) during simulations, to make...
- Mon Jul 31, 2023 6:07 pm
- Forum: Vensim
- Topic: Units Check whack-a-mole
- Replies: 9
- Views: 1151
Re: Units Check whack-a-mole
After a closer look, my conclusion is that the model is kind of bonkers. Normally units prevent conceptual errors like mixing up stocks and flows, but in this case I think the general difficulty in defining units is a big red flag in itself. It means that the model is rather far from an operational ...
- Mon Jul 31, 2023 4:36 pm
- Forum: Vensim
- Topic: Model calibration in Vensim PLE
- Replies: 2
- Views: 517
Re: Model calibration in Vensim PLE
No - PLE is really targeted at learning about dynamics.