Ventana software support forum

Is there any help for the MARKET MATCH function or is it still a prototype? I'm trying to use the FIND MARKET PRICE construct, but I need to know the (S1,M1), (S1,M2),(S2,M1),(S2,M2) allocation where Sx and Mx are changing (i.e. many-to-many). Then, I need to allocate that allocation to (M1,P1),(M1,...

The way I've used the FFT output from Vensim in Excel is to create discrete (DFT) intervals and normalize the sum of powers over those intervals to get a relative magnitude for each. Then, I use those values (which are essentially probabilities) to calculate entropy of the waveform which, as I menti...

Tony,

Sounds like you have some ideas how to do this? Actually, the FFT and DFT charts I've seen have been linear-linear.

Lou

Tony, Thanks again! I could use some help doing that, since I'm not really a programmer. Here's a free FFT (code and all), called Fastest Fourier Transform in the West (FFTW) at http://fftw.org/#documentation. They actually have a pre-complied DLL for these (http://www.fftw.org/install/windows.html)...

That would be great if it isn't too much trouble. I would think that since it's just a check box and it happens "on-the-fly" it should be a relatively straighforward calculation...although there are many ways to calculate a FFT/DFT. I don't know much more than you...only that they can subs...

Tony, Thanks for the prompt reply! Actually, Vensim is already doing what I need it to do...except that the data behind the calculation is not available to the model (except as an export of the table window...with Fourier Transform "turned on"). If you run the model that I attached, you'll...

Is there any way to calculate the Discrete Fourier Transform and use those values to calculate entropy INSIDE of Vensim (i.e. w/o having to generate the tabular FFT and export to Excel to complete the calculations)? If there was just a way to formulate an FFT, I think this could be accomplished...bu...

Yes, I see an out file (that only contains the better of the two results in the *endpoint.tab). So, I rename that to *.cin...and then what?

Thanks again in advance for your help!

I know there's a way to do it, but I've forgotten. I've calibrated a model and Vensim kicked out a *_endpoint.tab file containing two outcomes, which yielded about the same payoff. I'd like to load either as different cases (or whichever one is contained in the .vdf file asssociated with the run), b...

Lee,

Thanks...that worked...although at the fractions of a month I'm using, the model slows down quite a bit (I have to use time step = 0.015625). Maybe I can make it a weekly model...

Lou

I have a monthly model and want to use discrete functions, but I'm having a bit of trouble when using time units < 1 (i.e. fractions of a month). The Delay functions don't seem to pay attention to anything less than 1. For instance, Convey Time, Batch Time, etc. Is there some way to deal with this.....

My simulation won't run all the way to FINAL TIME in Game Mode. I have two buttons Run To End and Run (which runs each increment). If I hit Run to End, it just stops when it gets to 47 (out of 100). If I hit Run several times, it eventually gets to 47 and I get a Floating Point Error message. I can ...

Lee,

Thanks...that worked!!

Lou

Tony,

If you can find an answer for me before Monday, I'd greatly appreciate it. I'm trying to develop an interface to demonstrate Sable's capabilities to a customer.

Thanks,
Lou

Tony, Hi! Actually, the same thing happens with the Yakunda example app you provide. If you go into either Game Keeper or Synthesim mode and try to change the colors of the lines on either chart...you can't do it (or at least I can't). If you can tell me how to do it in that model, I should be able ...

In Developer, I'm trying to change line colors, chart-types, etc. in the Advanced 1 tab under Settings...but nothing seems to save. When I go back to the app, all the same "default" line colors and chart types are still there. How can I get all those great options to "stick"??