Search found 2965 matches

by tomfid
Mon Jul 06, 2020 3:08 pm
Forum: Vensim
Topic: Monthly Counter
Replies: 3
Views: 31

Re: Monthly Counter

Something like:
Month Index = Modulo(Time,One Month)+1 ~ dmnl
One Month == 1 ~ months
by tomfid
Sun Jul 05, 2020 4:11 pm
Forum: Vensim
Topic: migrating to the 64 bits version
Replies: 17
Views: 54

Re: migrating to the 64 bits version

What you are actually doing is selecting the path to the file,
... path to the directory really.
by tomfid
Sun Jul 05, 2020 4:10 pm
Forum: Vensim
Topic: migrating to the 64 bits version
Replies: 17
Views: 54

Re: migrating to the 64 bits version

The Visual Studio 2019 community edition is free, unless the "enterprise" criteria trips you up. https://visualstudio.microsoft.com/license-terms/mlt031819/ I'm not sure if v10 will work with x64 compilation, but the vcvars path may differ. Compare REM The following should work with Microsoft C/C++ ...
by tomfid
Sat Jul 04, 2020 6:04 pm
Forum: Vensim
Topic: migrating to the 64 bits version
Replies: 17
Views: 54

Re: migrating to the 64 bits version

Default location is c:\users\public\vensim\comp
by tomfid
Sat Jul 04, 2020 1:40 pm
Forum: Vensim
Topic: migrating to the 64 bits version
Replies: 17
Views: 54

Re: migrating to the 64 bits version

I use the 32 and 64 versions interchangeably on the same machine without really noticing a difference, so you should have no trouble. You can keep your compiler. The 64 version just uses a different variant of the mdl.bat. The only thing you might need to change is migrating any customized setting t...
by tomfid
Fri Jul 03, 2020 3:32 pm
Forum: Vensim
Topic: Vensim PLE does NOT be Installed
Replies: 3
Views: 28

Re: Vensim PLE does NOT be Installed

Hmmm... I can't find those threads myself.
by tomfid
Wed Jul 01, 2020 2:48 pm
Forum: Vensim
Topic: Create variable while the simulation is running
Replies: 9
Views: 50

Re: Create variable while the simulation is running

I think we need to know more about the problem we're trying to solve here. What is the motivation for discrete generating units? Is it so they can be turned on/off individually? So that capacity grows in steps instead of smoothly? Something else?
by tomfid
Wed Jul 01, 2020 1:07 pm
Forum: Vensim
Topic: Create variable while the simulation is running
Replies: 9
Views: 50

Re: Create variable while the simulation is running

In general, if total capacity is large, and individual units are small, adding discreteness is not going to add much to the model, unless perhaps the purpose is something short term and tactical. I would consider not disaggregating the units.
by tomfid
Wed Jul 01, 2020 1:06 pm
Forum: Vensim
Topic: Create variable while the simulation is running
Replies: 9
Views: 50

Re: Create variable while the simulation is running

If the units are all the same size, you don't really need them active discretely. You could instead have a variable representing number of units active, and with generation = N units active * unit size. If the units are discrete and come online in different years, then you could do something like: u...
by tomfid
Tue Jun 30, 2020 1:31 pm
Forum: Vensim
Topic: Varformat errors when exporting data
Replies: 12
Views: 61

Re: Varformat errors when exporting data

The only solution I've seen (but not tried) is to install the Win 8.1 SDK. So possibly a win7 sdk would also work. https://t.co/W0BrQzYQBw
by tomfid
Mon Jun 29, 2020 5:20 pm
Forum: Vensim
Topic: Is it possible to set a personnalized increment?
Replies: 3
Views: 33

Re: Is it possible to set a personnalized increment?

In other words, you want the constant slider to have a log scale? I agree that would be very useful.
by tomfid
Mon Jun 29, 2020 3:16 pm
Forum: Vensim
Topic: Varformat errors when exporting data
Replies: 12
Views: 61

Re: Varformat errors when exporting data

Are you using a command script or the menu?
by tomfid
Mon Jun 29, 2020 2:12 pm
Forum: Vensim
Topic: Vensim ODBC scenario selection via run name
Replies: 2
Views: 51

Re: Vensim ODBC scenario selection via run name

My suspicion is that you can use ! in a simple statement, as in the help example, but not in a complex select statement. If you use :FIELD statements instead of your WHERE / AND select, it should work.
by tomfid
Wed Jun 24, 2020 7:32 pm
Forum: Ventity
Topic: DELAY/Discrete Functions in Ventity
Replies: 4
Views: 174

Re: DELAY/Discrete Functions in Ventity

Here's an example of a hybrid approach (continuous population, agent doctors).
Dr Pt 1 (2).zip
(23.81 KiB) Downloaded 6 times
by tomfid
Wed Jun 24, 2020 5:44 pm
Forum: Ventity
Topic: DELAY/Discrete Functions in Ventity
Replies: 4
Views: 174

Re: DELAY/Discrete Functions in Ventity

Understood - thanks. I think you could model this particular case with DelayInformation, since it's essentially the same as a material delay, as long as the duration doesn't change within a simulation. This might also be interesting as a quasi-agent model, in which case you could have individual doc...
by tomfid
Wed Jun 24, 2020 2:34 pm
Forum: Vensim
Topic: Obtaining statistics for specific time period
Replies: 4
Views: 54

Re: Obtaining statistics for specific time period

Not so. You can use the Time Axis control in the Control Panel to restrict the period of interest, then use the stats tool as usual.
by tomfid
Wed Jun 24, 2020 4:24 am
Forum: Vensim
Topic: Unable to converge simultaneous loop at time
Replies: 7
Views: 119

Re: Unable to converge simultaneous loop at time

I deleted the post with the model. The rest is useful for others, if OK to leave it. If not, let us know.
by tomfid
Tue Jun 23, 2020 5:16 pm
Forum: Vensim
Topic: Unable to converge simultaneous loop at time
Replies: 7
Views: 119

Re: Unable to converge simultaneous loop at time

Another issue here seems to be that supply and demand are completely insensitive to the water shortage index. For example, a1 is constant as parameterized.
by tomfid
Tue Jun 23, 2020 2:36 pm
Forum: Vensim
Topic: A question about Find Zero Function
Replies: 2
Views: 48

Re: A question about Find Zero Function

I think the problem is that this is numerically cranky as formulated. Your NPV has a scale ~ investment, i.e. billions, while your x scale parameter is set to 1. Zeroing the npv to the nearest dollar is hard (and a waste of computation since the prospective NPV of a project is never certain). Set x ...
by tomfid
Thu Jun 18, 2020 11:59 am
Forum: Vensim
Topic: Typing the name of a variable using subscripts and superscripts
Replies: 1
Views: 89

Re: Typing the name of a variable using subscripts and superscripts

The short answer is, you can't - it's not supported. I don't know any text language that does. We do support unicode, so it's possible that there's some extended character set that would come close.
by tomfid
Sat Jun 13, 2020 2:41 pm
Forum: Vensim
Topic: Problem when copying a Vensim diagram
Replies: 3
Views: 103

Re: Problem when copying a Vensim diagram

Right - if you type "snip" in the search bar the snipping tool app comes up. <Windows>+<Shift>+S is a shortcut.

I also like "Jing," a free tool from TechSmith (publisher of Camtasia).
by tomfid
Fri Jun 12, 2020 9:02 pm
Forum: Vensim
Topic: Problem when copying a Vensim diagram
Replies: 3
Views: 103

Re: Problem when copying a Vensim diagram

This is an annoyance that came up recently with screens operating at high pixel pitches. Two options: - You can use the crop tool (in the Word/Ppt picture format ribbon) to eliminate the white space, then scale up the image. - Use the latest 8.1 version, and switch to the new sketch format (Tools me...
by tomfid
Fri Jun 12, 2020 12:56 pm
Forum: Vensim
Topic: Delay1 and Smooth
Replies: 4
Views: 103

Re: Delay1 and Smooth

https://www.vensim.com/documentation/fn_delay1.htm DELAY1=LV/delay time LV=INTEG(input-DELAY1,input*delay time) DELAY1I=LV/delay time LV=INTEG(input-DELAY1I,initial value*delay time) https://www.vensim.com/documentation/fn_smooth.htm SMOOTH=INTEG((input-SMOOTH)/delay time,input) SMOOTHI=INTEG((inpu...
by tomfid
Tue Jun 09, 2020 4:10 pm
Forum: Vensim
Topic: Vensim - GitHub Model Integration
Replies: 4
Views: 150

Re: Vensim - GitHub Model Integration

I think the problem is that your call to the cmd script is not using correct syntax. This is not entirely surprising, since the bits you've quoted from the Help are clearly using dated paths that are no longer valid in Win10. We'll have to update that. I haven't had a chance to try it, but I think t...
by tomfid
Thu Jun 04, 2020 3:44 pm
Forum: Ventity
Topic: DELAY/Discrete Functions in Ventity
Replies: 4
Views: 174

Re: DELAY/Discrete Functions in Ventity

The DelayInformation function provides a pipeline (infinite order) delay, much like DELAY FIXED. DELAY3 is also available. We haven't implemented other functions like DELAY CONVEYOR, mainly because there hasn't been demand. For my own use, I usually want to change the architecture of the model in Ve...