## Search found 1443 matches

Sun Nov 21, 2004 5:33 pm
Forum: Vensim
Topic: queue attrib
Replies: 7
Views: 6205

Hi I send a simplistic model for the attrib minimum function, the attrib in range needs more work because it does not work in a model more complicated and I have to transform it in a simple one. The model shows a level of cars with no cars at the beginning running for 7 months, one car being added e...
Fri Nov 19, 2004 2:22 pm
Forum: Vensim
Topic: queue attrib
Replies: 7
Views: 6205

### queue attrib

Hi The min function is still not working with the new version 5.4A. I cannot say if the quantity function is ok due to the definition which is highly imprecise. Ïn the definition there may be more than one result, unless the quantity is cumulated starting with the oldest elements which is not told i...
Fri Nov 12, 2004 6:59 pm
Forum: Vensim
Topic: reference mode
Replies: 1
Views: 3245

### replacing time with a variable in reference mode

Christina. If I understand correctly your question, you would like to replace time by population or food, to have sketched the relation between population and food? It will not be anymore a reference mode that sketches the relation of data and time. As for the possibility of doing it, it is more or ...
Fri Nov 12, 2004 1:31 pm
Forum: Vensim
Topic: calculating the intermediate sums of elements in an array
Replies: 2
Views: 3845

### summing problem

Hi Wilson Thanks for the help. I have learned too that a subscript if used as a constant holds the number it would have if used as an ordinary subscript starting at one. I used to declare a subscripted variable as I suscript id = 1,2,3,4,5,6,7,8,9,10 for that. Never saw that in the documentation. I ...
Thu Nov 11, 2004 5:32 pm
Forum: Vensim
Topic: calculating the intermediate sums of elements in an array
Replies: 2
Views: 3845

### calculating the intermediate sums of elements in an array

Hi every body Is there an easy way to calculate the sums of elements in a vector that change in time? The vector can be an auxiliary or a level. Exemple: the vector has three elements a1(t),a2(t) and a3(t), t being the time. I would like to SIMULTANEOUSLY (meaning in the same time period) have anoth...
Thu Nov 11, 2004 1:50 pm
Forum: Vensim
Topic: using queue attrib average
Replies: 1
Views: 3113

### using queue attrib average

Hi every body I use version 5.3 a of Vensim and I use the queue attrib average and queue attrib min functions that I suspect to work incorrectly with small numbers in the queue (1 or 2). Is there a problem with these functions? I have simulated with a spreadsheet the function and it gives different ...
Mon Oct 11, 2004 7:49 am
Forum: System Dynamics Discussion
Topic: QUERY Discrete-flow modeling for business simulation
Replies: 1
Views: 4531

### query discrete modelling

Hi Paul. I am glad that on some rare occasions, on this forum or on the SD list, people talk about business and not all the time about macro economics or macro something else. I think that with the macros, it must be easier to err from the initial objective and to build unrealistic models, the probl...
Sun Oct 10, 2004 4:51 pm
Forum: System Dynamics Discussion
Topic: Combining SD and statistics
Replies: 1
Views: 4137

### reply to SD and statistics

Hi Rutger. I am not sure at all to be of any help, but trying does not cost anything only my time. Let’s reformulate your problem as I have understood it. Maybe I am wrong. You have built so far a qualitative model that explains the cause, effects and feed back of your problem. Some of the effects a...
Mon Sep 20, 2004 5:46 pm
Forum: Vensim
Topic: Two dimensional lookup
Replies: 2
Views: 4020

### two dimensiional lookup

HI One way to manage a two dimensional lookup, whatever the kind of dimension (it looks like Time in your case), I have the same case but with price elasticities of different type of products, varying eventually with time which would make it a three dimensional lookup. One way is to simulate the loo...
Sat Sep 18, 2004 3:52 pm
Forum: Vensim
Topic: Modeling an In Transit effect
Replies: 4
Views: 5495

### in transit problem

Hi Did you try the delay conveyor for your in transit problem. It has many advantages. It is a pipeline delay, and you can vary the transit time evey time step and specify the position of the stuff on the conveyor at the start of the simulation as well as inputing every time step a different amount ...
Sun Sep 05, 2004 7:34 am
Forum: Vensim
Replies: 0
Views: 2553

About molecules Hi everybody Last year at the SD conference, somebody talked about a new version of molecules with a lot more of them. When I followed last year the real world distiance course of Jim Hines at WPI , he was already using this new version of molecules in the CD's. What has happened wit...
Sat Sep 04, 2004 2:45 pm
Forum: System Dynamics Discussion
Replies: 0
Views: 3514

Hi everybody Last year at the SD conference, somebody talked about a new version of molecules with a lot more of them. When I followed last year the real world distiance course of Jim Hines at WPI , he was already using this new version of molecules in the CD's. What has happened with this version. ...
Mon Aug 30, 2004 3:07 pm
Forum: Vensim
Topic: Transportation Matrix
Replies: 1
Views: 3065

Have you tried the two options with only 2 offices? Simplifying the problem to get insights is never a lost of time.

J.J. Laublé
Sun Aug 29, 2004 12:11 pm
Forum: Vensim
Topic: constants or data not showing correctly when forced by reali
Replies: 2
Views: 3863

### temporary solution for the dynamic of constants

Hi bob Thanks for your prompt reply! I will use the get xls look up to get data lookups. As for the dynamic of constants I will temporarily use a dummy variable for each constant or data constant equal to the constant and make reality check to change the values of the dummy variable. It is a bit cum...
Fri Aug 27, 2004 5:28 pm
Forum: Vensim
Topic: constants or data not showing correctly when forced by reali
Replies: 2
Views: 3863

### constants or data not showing correctly when forced by reali

Hi every body I have a little problem when I force constants or imported data to new values using reality check. I illustrate this with a simplistic model with one constant = 10 and a variable = 10 * constant = 100, running during 4 years. I check with reality check that if i divide the constant by ...
Sun Jun 27, 2004 3:07 pm
Forum: Vensim
Topic: how to run different Time Step in one model
Replies: 1
Views: 3027

### How to run different time step

Why don't you use the time step needed for your inside week constraints for all the model. It is easier to adapt the model to a smaller time step than to work with different parallel time steps.

J.J. Laublé
Fri Aug 29, 2003 9:20 am
Forum: Vensim
Topic: system dynamics mailing list still working?
Replies: 2
Views: 5847

### system dynamics mailing list still working?

Hi all I used to receive regularly about every day, the messages from the SD WEB list maintained by Bob Eberlein. The last message is from 13 days ago. What is happening? Are all the people sleeping, or digesting the late annual SD conference, or is the system broken or i have been taken tou of the ...
Sun Jul 20, 2003 10:34 am
Forum: Vensim
Topic: Molecules software
Replies: 1
Views: 4777

### Molecules software

Hi every one

In the documentation of the SD conference Mr Hines is mentionning a nex version of the molecules of about 200 molecules. The current one can load from Vensim holds about 50 of them.
How is it possible to get the 200 version?

Thanks and best regards.

J.J. Laublé