Search found 1239 matches

by LAUJJL
Fri Feb 08, 2019 9:17 am
Forum: Vensim
Topic: custom tables do not keep the datasets *1 after the model is saved
Replies: 3
Views: 237

Re: custom tables do not keep the datasets *1 after the model is saved

Hi I join the .mdl file. you will have to create two runs with different value of x and name them current1 and current2, and compare the two graphs essai and essai2. If I want to use the graph with the *1, I have to modify the graph to include the *1, lost during saving the model, something that is ...
by LAUJJL
Tue Feb 05, 2019 7:42 pm
Forum: Vensim
Topic: custom tables do not keep the datasets *1 after the model is saved
Replies: 3
Views: 237

custom tables do not keep the datasets *1 after the model is saved

Hi I join a simplistic model with two tables. the essai2 has the datasets named and the other has an *1 for the second table value. if one saves the model and one loads it again, the *1 has disappeared in the essai table, but not the named datasets in the essai2. Of course, I suppose that you will n...
by LAUJJL
Wed Jan 23, 2019 5:05 pm
Forum: Vensim
Topic: Loading data for constants with multiple subscripts
Replies: 5
Views: 344

Re: Loading data for constants with multiple subscripts

Hi I would too try uding the DLL functionnality using VBA. You can set values to constants using the simulate>setval function directly using subscripted variables or embedded do loops in VBA if you want to use the setvar function with simple variables. But this solution may be cumbersome, because I ...
by LAUJJL
Wed Jan 16, 2019 10:09 am
Forum: Vensim
Topic: What improvements would you like to see in Vensim?
Replies: 93
Views: 47677

Re: What improvements would you like to see in Vensim?

Hi John One cannot select different subscripts values from different equivalent subscripts. I have the same problem between different towns having different traffic between them. Of course it is always possible to build a report custom table and specify the different couple of subscripts you want to...
by LAUJJL
Sun Dec 30, 2018 5:57 pm
Forum: Vensim
Topic: 'Vec elm map' error
Replies: 8
Views: 563

Re: 'Vec elm map' error

Hi There are two difficulties in your formulation. The first is the correct use of the vector elm map and the possibility to use a simpler formula as explained in the link above or eventually the vector select explained by Tom. And once you are able to use a simpler formulation of the vector elm map...
by LAUJJL
Sun Dec 30, 2018 1:30 pm
Forum: Vensim
Topic: 'Vec elm map' error
Replies: 8
Views: 563

Re: 'Vec elm map' error

Hi

Avoid using the vector elm map function go to

viewtopic.php?f=2&t=3192&p=22055&hilit= ... map#p22055

It is good too setting the use stricte testing in the model<settings<units equiv window

Regards.

JJ
by LAUJJL
Fri Dec 21, 2018 12:42 pm
Forum: Vensim
Topic: Simple model in Vensim
Replies: 4
Views: 518

Re: Simple model in Vensim

Hi It is not only an implicit causes that does not appear in the equation. There are many cases where you need to put the stock in the equation. For instance if you go to the Vensim help and index and ask for the smooth function. You will see a stock and flow formulation of the smsooth function wher...
by LAUJJL
Thu Dec 13, 2018 11:16 am
Forum: Vensim
Topic: Model predictive control using Vensim?
Replies: 6
Views: 632

Re: Model predictive control using Vensim?

Hi I had a look at the greenhouse model. The conclusions do not improve the general understanding of the problem and propose classical already known solutions. But what seems strange is that the model does not study the real problem: the decision system, how it works, who take the decisions, can the...
by LAUJJL
Wed Nov 14, 2018 8:22 pm
Forum: Vensim
Topic: Changing the order of calculations
Replies: 10
Views: 784

Re: Changing the order of calculations

Hi Wanting to set the order of calculation, is like telling the computer to respect an order and another order at the same time, which is impossible to do. In fact, by writing the equations, you are telling the computer the order of calculation. For instance if d = a*b*c, before calculating d the pr...
by LAUJJL
Sun Nov 04, 2018 3:09 pm
Forum: Vensim
Topic: Aging chain with items taken out, on hold and put back
Replies: 20
Views: 1474

Re: Aging chain with items taken out, on hold and put back

There was a mistake in my previous post.
i did not mean deserve deeply the field, but was deeply detrimental to the field
by LAUJJL
Sun Nov 04, 2018 9:00 am
Forum: Vensim
Topic: Aging chain with items taken out, on hold and put back
Replies: 20
Views: 1474

Re: Aging chain with items taken out, on hold and put back

Hi Tom I totally agree with your point of view, except that you did not mention one of the characteristics of individual based methods: they are easier to test because they are a more exact representation of the reality making it possible to compare the exact reality to the model behaviour. Of cours...
by LAUJJL
Sat Nov 03, 2018 8:55 am
Forum: Vensim
Topic: Aging chain with items taken out, on hold and put back
Replies: 20
Views: 1474

Re: Aging chain with items taken out, on hold and put back

Hi
It is difficult to chose between different solutions, without a deep knowledge of the problem.
Is it a real problem or an academic one?
If it is a real problem, we do not know what the model has to improve: financial, technical issues?
Regards.
JJ
by LAUJJL
Fri Nov 02, 2018 7:53 pm
Forum: Vensim
Topic: Aging chain with items taken out, on hold and put back
Replies: 20
Views: 1474

Re: Aging chain with items taken out, on hold and put back

Hi In this model, you can generate two events every time step, and each event describes moving a definite quantity of widgets from one level to the other at a definite age. If you want to describe more events happening in a month, you must either reduce the time step, or add the subscript age to som...
by LAUJJL
Fri Nov 02, 2018 4:02 pm
Forum: Vensim
Topic: Aging chain with items taken out, on hold and put back
Replies: 20
Views: 1474

Re: Aging chain with items taken out, on hold and put back

Hi It looks like a partly discreet problem, as you deal with individual delays. I personally avoid delays, because you have no information about what is in the delay. It is too impossible to step back in games with delays. In this case I use arrays, where I have a total control on what is happening....
by LAUJJL
Sat Oct 06, 2018 3:51 pm
Forum: Vensim
Topic: managing the display of a custom table
Replies: 4
Views: 587

Re: managing the display of a custom table

Hi I am rather annoyed not to have any reply because I am testing policies with the gaming tool, using external data to avoid the random generator to be reset, every time that one changes a gaming variable or if one steps back. Without any answer i will treat this problem as a bug and will try to fi...
by LAUJJL
Wed Oct 03, 2018 4:47 pm
Forum: Vensim
Topic: managing the display of a custom table
Replies: 4
Views: 587

Re: managing the display of a custom table

I join a simplistic model that illustrates two problems. The first problem is relative to the question of my preceding post. Suppose that I run the model joined in game mode, and I want to survey the value of stock in the table drawn in the sketch. It show up to 9 values. If I run the model past the...
by LAUJJL
Wed Oct 03, 2018 1:06 pm
Forum: Vensim
Topic: managing the display of a custom table
Replies: 4
Views: 587

Re: managing the display of a custom table

Hi Tom

thank you for the reply.

I will study it;

Best regards.

JJ
by LAUJJL
Mon Oct 01, 2018 4:46 pm
Forum: Vensim
Topic: managing the display of a custom table
Replies: 4
Views: 587

managing the display of a custom table

Hi Is it possible to control the data to be displayed in a custom table especially when gaming? For instance if I have custom table showing a variable and the custom table has a relatively small length for lack of space available, and the custom table shows only three values corresponding to three s...
by LAUJJL
Wed Sep 26, 2018 10:34 am
Forum: Vensim
Topic: Beer game model without subscripts
Replies: 2
Views: 421

Re: Beer game model without subscripts

thank you very much.

It helps a lot.

Best regards.

JJ
by LAUJJL
Wed Sep 26, 2018 9:20 am
Forum: Vensim
Topic: Beer game model without subscripts
Replies: 2
Views: 421

Beer game model without subscripts

Hi Tom

Are there any explanations somewhere for the beer game without subscripts model found in your metasd model library.

For instance I cannot see the meaning of the R,W,D and F processings; What are these R,W,D and F meaning?

Best regards.

JJ
by LAUJJL
Tue Sep 18, 2018 9:18 am
Forum: Vensim
Topic: System of differential equations-- estimating parameters
Replies: 22
Views: 1603

Re: System of differential equations-- estimating parameters

Hi Simplifier. Another basic rule of SD that you do not respect: using constants with no significant name related to their meaning in the system that you pretend to describe. How can I understand a model where the author uses a1,b1,b2 etc.. without knowing what these constants are about? Best regard...
by LAUJJL
Tue Sep 18, 2018 8:53 am
Forum: Vensim
Topic: System of differential equations-- estimating parameters
Replies: 22
Views: 1603

Re: System of differential equations-- estimating parameters

Hi Simplifier You have little chance of ever finding a solution of your problem, using a powerful software that you apparently do not master because of too little practice. When one practices Vensim a bit one finds very quickly the utility of putting units in models, and then doing it becomes a seco...
by LAUJJL
Fri Aug 31, 2018 5:27 pm
Forum: Vensim
Topic: Export and import data between Vensim and Excel
Replies: 11
Views: 1144

Re: Export and import data between Vensim and Excel

HI

In which context are you building this model.

Will it be applied?

Regards.

JJ
by LAUJJL
Thu Aug 23, 2018 7:05 pm
Forum: Vensim
Topic: Export and import data between Vensim and Excel
Replies: 11
Views: 1144

Re: Export and import data between Vensim and Excel

Hi

what is your problem?

Every year, I suppose that you have to take some décisions.

which décisions?

How is the cash flow of the year dependant from past Investments?

it would be useful to upload a very small model to illustrate your problem.

Regards.

JJ
by LAUJJL
Thu Aug 23, 2018 12:47 pm
Forum: Vensim
Topic: Export and import data between Vensim and Excel
Replies: 11
Views: 1144

Re: Export and import data between Vensim and Excel

why do you want to calculate the IRR out of Vensim? Because the function exists in Excel? It is much simpler to calculate the IRR in Vensim, than exchanging data between vensim and excel. to calculate the IRR, you must find the zero of the NPV, that i think is calculated in Vensim. to find the rate ...