Hi
Here is the complete challenge with an excel file having the values of the challenge and the modified model that reads the value from the excel file. What else do you need as this works well? You can replace the sum that I use by a vector lookup as Tom proposes.
JJ
Search found 1455 matches
- Mon Nov 11, 2024 9:04 am
- Forum: Vensim
- Topic: Reiterating Data
- Replies: 17
- Views: 337
- Mon Nov 11, 2024 8:11 am
- Forum: Vensim
- Topic: Simultaneous workaround
- Replies: 5
- Views: 66
Re: Simultaneous workaround
Simultaneous and find zero work like a black box because you don't see the intermediate results that lead to eventual convergence or not. I often prefer to use a vector in which I store the intermediate results that I calculate myself so that they converge. In short, I make my own simultaneous or fi...
- Thu Nov 07, 2024 3:10 pm
- Forum: Vensim
- Topic: units for %
- Replies: 10
- Views: 192
Re: units for %
the epidemic.vdfx file
- Thu Nov 07, 2024 3:05 pm
- Forum: Vensim
- Topic: units for %
- Replies: 10
- Views: 192
Re: units for %
Hi Not many Vensim users are familiar with this strict testing feature. For example, if you add 5 to a variable and that variable has a dimension, e.g. people/year, Vensim assumes that 5 has a dimension equal to that of the variable, unless the strict test is on, in which case there is a unit error ...
- Thu Nov 07, 2024 7:53 am
- Forum: Vensim
- Topic: Reiterating Data
- Replies: 17
- Views: 337
Re: Reiterating Data
Hi Joined the model with the 10 values. i do not use 'sub" as a value for the index as it probably looks weird for you. Subscripts in Vensim are a bit difficult to understand especially the mapping system; But once you have understood it you will be able to model any logic without the use of an...
- Wed Nov 06, 2024 7:43 pm
- Forum: Vensim
- Topic: units for %
- Replies: 10
- Views: 192
Re: units for %
If you click on model settings and units, on the top of the window you can check use stict testing. i just wanted to know if you use strict testing or not.
JJ
JJ
- Wed Nov 06, 2024 5:00 pm
- Forum: Vensim
- Topic: Reiterating Data
- Replies: 17
- Views: 337
Re: Reiterating Data
Hi Here is the model. i have given artitrary valeus to the array that has to be dosnladed from the excel file, something that is easy to do. i do not know if it is quicker but the utility is that the process is clearer. One downlaods first the data in an array and then one makes at each time the val...
- Wed Nov 06, 2024 11:24 am
- Forum: Vensim
- Topic: units for %
- Replies: 10
- Views: 192
Re: units for %
In this thread, there is a question of units. Are these strict or non-strict unit tests?
JJ
JJ
- Wed Nov 06, 2024 11:13 am
- Forum: System Dynamics Discussion
- Topic: modelling GDP
- Replies: 1
- Views: 87
Re: modelling GDP
Just one remark: your GDP is not exogenous being modeled, but endogenous. For the rest, your model assumes an increase in GDP proportional to the GDP itself, which automatically generates exponential growth.
JJ
JJ
- Mon Nov 04, 2024 9:21 am
- Forum: Vensim
- Topic: Reiterating Data
- Replies: 17
- Views: 337
Re: Reiterating Data
I would try downkoading the 8760 data in an array first and then use the modulo to make each time point equal to the corresponding element in the array
JJ
JJ
- Sun Oct 27, 2024 8:38 pm
- Forum: Vensim
- Topic: SDEverywhere vs. reality checks
- Replies: 5
- Views: 497
Re: SDEverywhere vs. reality checks
Hi I have been using 'reality checks' for years. They have two disadvantages; they are interpreted then slow and at the time, they could not be run in batch mode for example by launching multiple runs from Excel using DLLs. It may be possible that we can now run reality checks in batch mode with new...
- Sat Sep 28, 2024 11:08 am
- Forum: Ventity
- Topic: Modelica Simulation - Emmanuel Katto
- Replies: 2
- Views: 1021
Re: Modelica Simulation - Emmanuel Katto
Hi
Guido Wolf Reichert is a modelica specialist using system dunamics too, member of the SDS some years ago. But there is now some time that I had no news from him. You can either browse google with his name or use: gwr@bsl-support.de if it still works.
Best
JJ
Guido Wolf Reichert is a modelica specialist using system dunamics too, member of the SDS some years ago. But there is now some time that I had no news from him. You can either browse google with his name or use: gwr@bsl-support.de if it still works.
Best
JJ
- Tue Sep 10, 2024 5:54 pm
- Forum: Vensim
- Topic: cannot change the font of the equation editor
- Replies: 8
- Views: 1986
Re: cannot change the font of the equation editor
If i set the options fonts to 8, in the equation editor, the numbers are very small. with 9, it becomes much better. with 10, there is a very small increase in size and with 11, the size in the editor is slightly better and the bigger I can get. But with 12, the size in the editor is again very smal...
- Tue Sep 10, 2024 11:21 am
- Forum: Vensim
- Topic: cannot change the font of the equation editor
- Replies: 8
- Views: 1986
Re: cannot change the font of the equation editor
i have copied the numbers on word and verified the size. it is 8. But if i change the size to Arial 12, in the equation editor, there is no change
- Tue Sep 10, 2024 8:23 am
- Forum: Vensim
- Topic: cannot change the font of the equation editor
- Replies: 8
- Views: 1986
Re: cannot change the font of the equation editor
I have selected different size points. For the moment 8 the smallest possible.
- Mon Sep 09, 2024 1:53 pm
- Forum: Vensim
- Topic: cannot change the font of the equation editor
- Replies: 8
- Views: 1986
Re: cannot change the font of the equation editor
I have made the font Arial normal different size using tools>options>fonts>equation editor avery time savied and exited Vensim. It has not changed anything.
- Sun Sep 08, 2024 1:27 pm
- Forum: Vensim
- Topic: cannot change the font of the equation editor
- Replies: 8
- Views: 1986
cannot change the font of the equation editor
Hi
The size of the fonts in the equation editor are very small and I do not know how to change them. i tried options and fonts and equation editor, and the size is ok but the editor stays the same.
JJ
The size of the fonts in the equation editor are very small and I do not know how to change them. i tried options and fonts and equation editor, and the size is ok but the editor stays the same.
JJ
- Mon Jul 29, 2024 5:30 pm
- Forum: Vensim
- Topic: custom tables do not save time running down
- Replies: 1
- Views: 2760
custom tables do not save time running down
HI
If one click the time run down button and one saves a custom graph if one edits it again the run down button is no more clicked. this makes mipossible to use a custom graph with time running down. It works with any model and any custom graph. with the new gui.
Regards.
JJ
If one click the time run down button and one saves a custom graph if one edits it again the run down button is no more clicked. this makes mipossible to use a custom graph with time running down. It works with any model and any custom graph. with the new gui.
Regards.
JJ
- Sat Jul 13, 2024 9:27 am
- Forum: Vensim
- Topic: ack of simulation results
- Replies: 5
- Views: 4674
Re: ack of simulation results
There is a bug in your model. To find it you must understand why Cena stays equal to Cena rynkowa all the time. Start at time 0, and verify all the variables and their equations starting from Cena using the uses tree that have an influence on Cena rynkowa. if you do that with care, you will find the...
- Wed Jun 19, 2024 3:53 pm
- Forum: Vensim
- Topic: Population Example with Conveyors
- Replies: 4
- Views: 4256
Re: Population Example with Conveyors
The two errors in the maturations happen just before the levels reach zéro. Some formulation errors generate strange behaviour in limit conditions. There is probably an error somewhere in the model. There is too an error in the population view of the world 3 model where the error disappears if one s...
- Wed Jun 19, 2024 11:37 am
- Forum: Vensim
- Topic: Population Example with Conveyors
- Replies: 4
- Views: 4256
Re: Population Example with Conveyors
The use of a minimum in the 'young deaths' looks strange. Logically the maturation should calculate how many young people still alive are getting older; And this calculation should not be able to force the level to be negative. One must decide if the young people becoming young adults are still belo...
- Thu Jun 13, 2024 4:45 pm
- Forum: Vensim
- Topic: control button not working the same way in DSS and reader
- Replies: 2
- Views: 3523
Re: control button not working the same way in DSS and reader
The model seems to work the same way than the DSS. Going to the view view 2 seems to be a bug.
it would be useful to have somewhere an explanation of the 9 added controls plus some exemples like the Venapps examples.
Regards.
JJ
it would be useful to have somewhere an explanation of the 9 added controls plus some exemples like the Venapps examples.
Regards.
JJ
- Wed Jun 12, 2024 4:41 pm
- Forum: Vensim
- Topic: control button not working the same way in DSS and reader
- Replies: 2
- Views: 3523
control button not working the same way in DSS and reader
Hi The new DSS version has now all the controls available. I join two models that have both a button control. The first model essai.mdl has a button whose name is ‘go to next view’ and with a control that effectively goes to the next view. If one publishes the model into a .vpmx model and one opens ...
- Tue May 14, 2024 9:32 am
- Forum: Vensim
- Topic: System Dynamics definition
- Replies: 10
- Views: 4222
Re: System Dynamics definition
The less math and more life experience.
- Tue May 14, 2024 8:15 am
- Forum: Vensim
- Topic: System Dynamics definition
- Replies: 10
- Views: 4222
Re: System Dynamics definition
Hi
I think that advanced knowledge like control theory is more harmful than helpful because it may lead to think that the more math the better. I think that the less math the better.
JJ
I think that advanced knowledge like control theory is more harmful than helpful because it may lead to think that the more math the better. I think that the less math the better.
JJ