Search found 95 matches
- Tue Jun 16, 2015 10:36 pm
- Forum: Vensim
- Topic: GET DIRECT functions treat negative numbers as positive
- Replies: 7
- Views: 4433
Re: GET DIRECT functions treat negative numbers as positive
Thanks so much! The upcoming fix is greatly appreciated!
- Tue Jun 16, 2015 7:12 pm
- Forum: Vensim
- Topic: GET DIRECT functions treat negative numbers as positive
- Replies: 7
- Views: 4433
GET DIRECT functions treat negative numbers as positive
Hello everyone, I am using the GET DIRECT CONSTANTS function to load data into some variables in my model from CSV files. I realized that negative numbers in the CSV file are being interpreted as positive numbers when being read into Vensim. I've tried using both comma-delimited and tab-delimited te...
- Thu Mar 05, 2015 9:23 pm
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
This is a bug report. On Windows, when you double-click on a model file, Vensim fails to open the model if there is an occurrence of the right-hand parenthesis character- that is, ")" - anywhere in the path leading to the model or in the model name itself. It launches Vensim, and then Vens...
- Mon Jan 12, 2015 7:59 pm
- Forum: Vensim
- Topic: Hardware and OS to Optimize Scripted Runs
- Replies: 5
- Views: 4046
Re: Hardware and OS to Optimize Scripted Runs
I wanted to post an update to this thread, because we've done a lot of testing now, and I have some answers that might be helpful to the Vensim development team and to future Vensim users that want to use lengthy command scripts. I discussed two problems in this thread: a slowdown as more and more r...
- Mon Dec 08, 2014 7:34 pm
- Forum: Vensim
- Topic: Hardware and OS to Optimize Scripted Runs
- Replies: 5
- Views: 4046
Re: Hardware and OS to Optimize Scripted Runs
Thank you so much, JJ and Administrator, for the advice on speeding up the runs. I really appreciate it. One can too use sensitivity analysis to estimate the effect of the structural parameters on the payoff. I have used the built-in Monte Carlo tool in Vensim to investigate sensitivity of specific ...
- Fri Dec 05, 2014 10:04 pm
- Forum: Vensim
- Topic: Hardware and OS to Optimize Scripted Runs
- Replies: 5
- Views: 4046
Hardware and OS to Optimize Scripted Runs
Hello everyone, We have a large model that calculates the effects of up to 35 policies (each set via its own variable in Vensim) on CO2 emissions and on cash flow in the economy. We wish to run this model many thousands of times, varying the policy settings, and outputting results for specific varia...
- Mon Oct 20, 2014 9:15 pm
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
My suggestion #5: It would be nice if Vensim recognized comments in command files (with .cmd extension), rather than trying to parse them and then generating an error. In a Windows command file (which also uses the .cmd extension), the syntax for a comment is to start a line with "rem" or ...
- Thu Aug 14, 2014 7:49 pm
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
My suggestion #4: It would be nice to allow the user to specify which subscripts the ALLOCATE AVAILABLE function should act on, rather than restricting it to a single subscript. Perhaps the user could use the "!" symbol to designate which subscripts should be included. Here's where this is...
- Tue Jul 08, 2014 6:48 pm
- Forum: Vensim
- Topic: Contractor Opportunity [No Longer Accepting Applications]
- Replies: 2
- Views: 2134
Re: 6 Month+ Vensim Contractor Opportunity
That's a great idea. I think I'll make the posts myself in those other places- that way I can edit/remove them when they are no longer applicable. Thank you!
- Tue Jul 08, 2014 12:02 am
- Forum: Vensim
- Topic: Contractor Opportunity [No Longer Accepting Applications]
- Replies: 2
- Views: 2134
Contractor Opportunity [No Longer Accepting Applications]
This post originally advertised a 6+ Month Vensim contractor opportunity. I am no longer accepting applications for the contractor position at this time.
Jeff Rissman
Jeff Rissman
- Mon Jul 07, 2014 11:28 pm
- Forum: Vensim
- Topic: Difficulty Handling Matrix Operation
- Replies: 7
- Views: 4561
Re: Difficulty Handling Matrix Operation
Thanks, everyone, for the further advice. It definitely sounds like avoiding external functions is best. I've thought of a simplification that is satisfactory for this model and have implemented it. This aspect seems to be working. When it is done, this model will be released publicly for free (anyo...
- Wed Jul 02, 2014 7:09 pm
- Forum: Vensim
- Topic: Difficulty Handling Matrix Operation
- Replies: 7
- Views: 4561
Re: Difficulty Handling Matrix Operation
Thank you- these replies are helpful. Using an ALLOC approach might work here. I agree that the [source x source] matrix probably isn't needed. The model is pretty big at this point, and I can't post it, but if I end up needing more specific advice, I could construct a small model that demonstrates ...
- Wed Jul 02, 2014 5:13 am
- Forum: Vensim
- Topic: Difficulty Handling Matrix Operation
- Replies: 7
- Views: 4561
Difficulty Handling Matrix Operation
Hello everyone, I've been working on an energy system model and have run into something tricky which seems like it ought not to be so difficult. The relevant part of the model is trying to determine if various types of power plants (coal, natural gas, nuclear, hydro, wind, solar, and biomass) should...
- Tue Apr 01, 2014 12:35 am
- Forum: Vensim
- Topic: Approaches for Different Units by Subscript Value?
- Replies: 2
- Views: 1972
Re: Approaches for Different Units by Subscript Value?
Thanks for the quick reply! I think I'll go ahead and implement it that way.
- Mon Mar 31, 2014 11:34 pm
- Forum: Vensim
- Topic: Approaches for Different Units by Subscript Value?
- Replies: 2
- Views: 1972
Approaches for Different Units by Subscript Value?
Hello Vensim community, I have a quick question. I have a model of the transportation sector where the units should be different across the values of a "cargo type" subscript (with values "passengers" and "freight"). This occurs in many variables in the model, and it us...
- Wed Dec 04, 2013 7:00 am
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
My suggestion #3: Please allow the ALLOCATE AVAILABLE function to work properly when given a sub-range, rather than a complete subscript range. This incompatibility was discussed in a thread on this forum at http://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=4991&p=17188&hilit=all...
- Wed Nov 27, 2013 11:18 pm
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
Here's another issue that I've run into repeatedly. When you copy a variable that includes in-line comments (e.g. inside curly braces in the "Equations" field, not in the "Comment" field) and paste the variable with "Replicate" mode (e.g. using a prefix or suffix, so it...
- Thu Nov 21, 2013 10:56 pm
- Forum: Vensim
- Topic: What improvements would you like to see in Vensim?
- Replies: 150
- Views: 14773974
Re: What improvements would you like to see in Vensim?
This is a small thing, but it would be great if a user could select multiple objects by dragging a box around them (while holding shift) when he/she already has one or more objects selected. Currently, Vensim lets you drag a box to make the initial selection, but after that, objects must be added to...
- Wed Oct 16, 2013 11:02 pm
- Forum: Vensim
- Topic: Subscripts Not Displaying in Subscripts Panel
- Replies: 4
- Views: 3404
Re: Subscripts Not Displaying in Subscripts Panel
Thanks, Tom. It does seem to be treating my second subscript as a subrange of the first subscript because they share an element name. When you look at the "Full View" of the Subscripts panel, it does show the name of my second subscript ("Fuel Type Demanded") in the "Subrang...
- Wed Oct 16, 2013 6:32 pm
- Forum: Vensim
- Topic: Subscripts Not Displaying in Subscripts Panel
- Replies: 4
- Views: 3404
Subscripts Not Displaying in Subscripts Panel
Hello everyone, I think that I'm encountering a bug that I would like to report, but I would also like advice if there is something I am doing wrong. After I've made at least one subscript, any additional subscripts I make that contain at least one value with the same name as a value contained in a ...