Search found 2425 matches

by tomfid
Tue Jan 15, 2019 8:05 pm
Forum: Ventity
Topic: Games in Ventity?
Replies: 2
Views: 7

Re: Games in Ventity?

I think it might be possible when you run a Ventity model on Forio, but I'm not sure.
by tomfid
Tue Jan 15, 2019 8:04 pm
Forum: Ventity
Topic: Games in Ventity?
Replies: 2
Views: 7

Re: Games in Ventity?

It hasn't been on the list, but it is now.
by tomfid
Sat Jan 12, 2019 3:44 pm
Forum: Vensim
Topic: Export
Replies: 1
Views: 14

Re: Export

I think that's an Excel column limitation, not a Vensim limit.

Try switching to tab-delimited or csv, or switch time from down to across if you have more variables than times.

You can use a savelist and data export interval (or saveper) to restrict the size of the dataset.
by tomfid
Mon Jan 07, 2019 8:41 pm
Forum: Vensim
Topic: Export to PDF
Replies: 4
Views: 42

Re: Export to PDF

You could use a pdf print driver, like PdfCreator.
by tomfid
Sun Jan 06, 2019 4:37 pm
Forum: Vensim
Topic: Not enough memory error
Replies: 4
Views: 47

Re: Not enough memory error

Wow - this is huge to run with such a fine time step - it's generating something like 200 billion floating point numbers. I think you probably need 64-bit, even with other strategies like using a savelist to reduce storage.

What is this about?
by tomfid
Sat Jan 05, 2019 6:54 pm
Forum: Vensim
Topic: Not enough memory error
Replies: 4
Views: 47

Re: Not enough memory error

How big is the model? (You can find the equation counts on the Model>Settings>Info tab.)

One option would be to switch to the 64-bit version.
by tomfid
Sat Jan 05, 2019 3:19 pm
Forum: Vensim
Topic: Dataset current already exists. do you want overwrite it?
Replies: 4
Views: 35

Re: Dataset current already exists. do you want overwrite it?

It won't appear if you change the run name each time. You can disable it in command scripts with the NOINTERACTION command.
by tomfid
Wed Jan 02, 2019 3:30 pm
Forum: Vensim
Topic: a stock with zero slope
Replies: 6
Views: 69

Re: a stock with zero slope

If the stock of actual quality is essentially a step function, its net flow must be a discrete event, like a PULSE.
by tomfid
Thu Dec 27, 2018 5:07 pm
Forum: Vensim
Topic: a Question about units
Replies: 2
Views: 62

Re: a Question about units

People and Person are really the same unit, so they cancel out. Use Model>Settings>Units Equiv to define people,person as synonyms if you're getting an error.
by tomfid
Sun Dec 23, 2018 3:31 pm
Forum: Ventity
Topic: Optimisation and optimisation control functions
Replies: 2
Views: 163

Re: Optimisation and optimisation control functions

I'm not entirely sure what you're looking for, but Ventity already has basic optimization capabilities, with the Powell optimizer, which can be used on multiple entities. It lacks some of Vensim's depth, like MCMC but much is possible already.
by tomfid
Fri Dec 21, 2018 6:11 pm
Forum: Vensim
Topic: Simple model in Vensim
Replies: 4
Views: 215

Re: Simple model in Vensim

The stock name is there because it is a valid input. For example, an alternative implementation of a SMOOTH is: smoothed input = INTEG( (input-smoothed input)/smoothing time, initial input ) However ... it is true that if you do this, your diagram is likely to break standard stock-flow diagramming c...
by tomfid
Fri Dec 21, 2018 6:06 pm
Forum: Ventity
Topic: multiple variables in sliders
Replies: 2
Views: 152

Re: multiple variables in sliders

Hi -

The slider shown has multiple entities for one variable, which is a function of the input data.

Extending the slider control to include multiple variables is on the todo list. We'll be discussing priorities after the holidays, so I'll bump this up a notch.

Tom
by tomfid
Wed Dec 19, 2018 5:56 pm
Forum: Ventity
Topic: Ventity 2.0.1 Released
Replies: 0
Views: 181

Ventity 2.0.1 Released

Ventity 2.0.1 is now available, and it's a big upgrade. See http://ventity.biz/ventity-2-0-1-released/ for details.
by tomfid
Tue Dec 18, 2018 9:47 pm
Forum: Vensim
Topic: Model predictive control using Vensim?
Replies: 6
Views: 256

Re: Model predictive control using Vensim?

I can think of several examples, none of which are readily shareable. However, the basic code needed is quite simple. The hard part, if there is one, is setting up the infrastructure to feed data. You could definitely run into convergence problems, but that's largely a matter of model robustness. Th...
by tomfid
Tue Dec 18, 2018 5:47 pm
Forum: Vensim
Topic: 7 day average daily max
Replies: 8
Views: 253

Re: 7 day average daily max

Try this:
moving max.mdl
(4.77 KiB) Downloaded 29 times
by tomfid
Tue Dec 18, 2018 5:25 pm
Forum: Vensim
Topic: 7 day average daily max
Replies: 8
Views: 253

Re: 7 day average daily max

Actually, it sounds like what you want is weeklyAverage( dailyMax ) - I described weeklyMax( dailyAverage ). Should be similar though.
by tomfid
Tue Dec 18, 2018 2:53 pm
Forum: Vensim
Topic: 7 day average daily max
Replies: 8
Views: 253

Re: 7 day average daily max

Maintaining quantiles over moving windows is generally a hard problem - there are low-memory approximate solutions, but they're complicated. I think the solution here is probably to create an array dimension for the seven days, and store daily values in it. Then you can retrieve the max value with V...
by tomfid
Mon Dec 03, 2018 2:15 pm
Forum: Vensim
Topic: Graphics Axis
Replies: 4
Views: 196

Re: Graphics Axis

Or, for transient changes, you can just drag on the graph to zoom in.
by tomfid
Mon Dec 03, 2018 2:15 pm
Forum: Vensim
Topic: Graphics Axis
Replies: 4
Views: 196

Re: Graphics Axis

Use the Control Panel's Time-Axis tab.
by tomfid
Sat Dec 01, 2018 12:19 am
Forum: Vensim
Topic: Strange result with a constant in Vensim
Replies: 4
Views: 221

Re: Strange result with a constant in Vensim

Cool. That was too easy.
by tomfid
Fri Nov 30, 2018 11:08 pm
Forum: Vensim
Topic: Strange result with a constant in Vensim
Replies: 4
Views: 221

Re: Strange result with a constant in Vensim

Could a .cin file be overriding the values?

When all the values are the same, you only need one equation. You could supply the distinct values by .cin override. (This is surely not the cause though.)
by tomfid
Wed Nov 28, 2018 2:49 pm
Forum: Vensim
Topic: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files
Replies: 16
Views: 447

Re: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files

I recall discussing this with Bob ages ago. It may be that there are already two modes (write everything, write only interactive changes) but the trigger for the latter is somehow getting missed in some cases.
by tomfid
Wed Nov 28, 2018 1:53 pm
Forum: Vensim
Topic: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files
Replies: 16
Views: 447

Re: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files

When you write a cin file from synthesim, you get everything as well. Maybe we need a new "update" concept for .cin files, that overwrites an existing template (existing cin or maybe lst) with new values only for the variables found.
by tomfid
Wed Nov 28, 2018 12:23 am
Forum: Vensim
Topic: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files
Replies: 16
Views: 447

Re: Bug Report: Model Reader (but not DSS) Writes Junk into .cin Files

Strange. We'll check it out. Thanks for the thorough report!