Ventana software support forum

Tom, great to hear that and I am looking forward to see the :Hold Backward: and :Look Forward: data variables being displayed accurately. While the mistery of variables not disappearing in a new view has been resolved (template view) I do struggle to find any documentation on those items. In the Ven...

A short update to my last post: The problem described under (1.) has been resolved. For some reason the unconscious parts of me must have marked "Use Template View" - a feature I have never used so far... So there just remains the issue of bringing String Vars into the equation editor if t...

Dear Administrator (Tony? - a name is so much more personal :wink: ), I agree with making structure explicit and may thus use hiding to 'unclutter' model structure. Nonetheless in this special case the structure is only a work around the false display... While 'playing' with string vars I noted real...

Thanks, Tom. That is really helpful - next to all the other stuff that can be found on your blog (I liked the examples of 'misguided statistical argumentation' -> Paul Krugman after all is mapping Deficit to Debt !!). Great work, keep it up.

Guido

I would have the following additions (I have not checked for duplicity so someone may have suggested this also): I would like to have the graph toll and the strip graph tool show a data variable that has been read in as :HOLD BACKWARD: or :LOOK FORWARD: in its correct form, e.g. as a step-variable i...

Tom and Tony(?), thanks for the responses which unfortunately are not solving my problem: I wanted to hide 'unnecessary' model structure and having to include string vars does do the exact opposite. I really wonder why literals are not accepted as input to a macro - shouldn't that be made possible? ...

Dear Support: I wanted to write a very simple Macro to achieve the following: When reading in a variable as say :HOLD BACKWARD: The variable will not be displayed as a step function. It will only be displayed as a step function when passed to another variable like varDisplayHold = varHold. Unfortuna...

Thank you, Tom, for that advice; I had indeed not switched on the display of messages for some reason. I will probably use the Delay N from now on much like using a zidz or xidz for "safety" while (of course) keeping integration step and method in mind.

Kind regards,

Guido

Just another thought and general question: What is the philosophy behind having DELAY3 not take care of numerical issues and give a warning message while DELAY N does? Would you sugest to use DELAY N (with the order set to 3) instead of DELAY3 in most cases since it will be on the safe side? And if ...

Hello Tom, thank you for the answer and I am glad there is no issue with the function. I have located the relevant information in the documentation in the meantime also. What is an issue though is that I am not getting any runtime messages; at least when I run the model as it is Vensim DSS 6.0.0.1 s...

Dear all, I recently built an experimental model which used a standard formulation for orders and delivery. This is usually modeled a a flow of orders with an orderrate flowing into a stock called backlog which is then drained by deliveries . In the model that I had built I used a DELAY3 - function ...

Hi John, you are as it sounds working on a similar problem that we have been working on here. In our case it was classical, zone-based transportation modeling. I had this issue (dealing with bigger models) up in a post last year, so you might take a look: http://www.ventanasystems.co.uk/forum/viewto...

Thank you both, Tony and Tom, for taking your time to get some answers up. I am happy to find that this is a legitimate question and it should probably address other people's needs, too. More so as we should expect to see more 64 Bit applications out there. As far as running the 32 Bit DLL from VBA ...

I would like to install Windows Office 64 Bit in order to avoid the many compatibility errors popping up when switching between 32 Bit and 64 Bit applications and in order to make use of the 'luxuious amount of RAM' my machine has. There remains of course a critical question: Will I risk Vensim not ...

Tom,

thank you very much for the research and your explanation.

Kind regards,

Guido

I just found in Dogan, Bootstrapping for Confidence Interval Estimation, in: SDR 23 (2007) 4 that the way Vensim uses the likelihood ratio method to come up with confidence intervals for parameter estimates in calibration is not compatible with standard econometrics texts (Dogan references Greene, 2...

For completeness and correctness: The 'oficial' solution I now have seen posted actually is using ReinstallNet thus: Needs["NETLink`"] ReinstallNET["Force32Bit" -> True] For easy reference to how DLL functions are called from Mathematica: http://reference.wolfram.com/mathematica/...

Here is some first advice for those interested in calling Vensim via the Vensim DLL from Mathematica in order to do experiments, analyses and other stuff which neatly combines the great graphics and analysis-power of Mathematica and the ease of formulating dynamical systems in Vensim. Essentially th...

Yes, the savelist is necessary as the file will blow otherwise. The practice of keeping a program or model separated from the data it uses seems to me quite reasonable and is suggested in the Vensim reference itself. If you take a look at a model the exogenous vars that need data will be constants, ...

Here is the error message that I am getting: Using the save list Datamodel.lst - not all variables will show behavior ERROR: -Effect of parking space f- not of right type. Cannot be saved. Effect of parking space f. ^. Line 23 of file datamodel.lst. It seems that a lookup is simply not allowed on a ...

Hi,

I am using a data-model to generate exogenous inputs to a model. I am getting an error though when I try to put a lookup var that is in the data-model on the savelist. Is there a way around?

Kind regards,

Guido

Hi, even though it may be a bit heretical I would like to draw your attention to a leading competitor (Powersim) that has recently released the Studio 9: http://www.powersim.com/main/products___services/powersim_products/premium/ http://www.powersim.com/main/products___services/powersim_products/com...

I had enquired this some time ago myself. As far as I can see there might be some error with the first name of the ominous " William Wood". The problem addressed seems to be referred to in the literature as the dispatch problem and the algorithm thus as a dispatching algorithm. I have foun...

Dear all: Although this is actually not my part I will here state what I have been told by the support: The issue is known. The software developpers had decided to raise the sensitivity for simultaneous equation errors, as far as I am told, which unfortunately turns fowl now with the Vector Elm Map ...

Hi JJ, while I indeed have to admire the intricacies of your formulations in order to correctly capture losses and gains fulfilling the postulate of mass balance I would still say that this is in vain. If you take a look at the modified model of yours that I have enclosed the comparision with the DE...