Search found 13 matches
- 4 months ago
- Forum: Modeling
- Topic: Writing model tests - best practices
- Replies: 4
- Views: 433
Re: Writing model tests - best practices
Thanks Steve and Renger for your replies, So again a short note about our current procedure: We don't do the tests manually anymore, as we wrote an R-script that automates the process: 1) On every SVN update, a post-commit hook on the SVN server runs the R-script, which in turn runs the GAMS batch f...
- 4 months ago
- Forum: Modeling
- Topic: Writing model tests - best practices
- Replies: 4
- Views: 433
Writing model tests - best practices
Here at our institute, we work on a couple of (larger scale) economics related GAMS models. Different teams, involved in different projects make adaptations to the models in order to answer their specific research questions. The models are equipped with a Graphical User Interface (GUI), and are vers...
- 7 months ago
- Forum: Modeling
- Topic: CPLEX does not find true optimum despite optcr=0
- Replies: 2
- Views: 443
Re: CPLEX does not find true optimum despite optcr=0
Thanks @ameeraus for the reply and the elegant solution to my problem. As you might have guessed, I totally oversaw that my .fx was actually resetting the lower bound of the variable. If I would have actually set a lower bound of 1 (instead of fixing it), I would have received a matrix error stating...
- 7 months ago
- Forum: Modeling
- Topic: CPLEX does not find true optimum despite optcr=0
- Replies: 2
- Views: 443
CPLEX does not find true optimum despite optcr=0
Hi everyone, In a MIP model with option optCR=0; , I face the problem that CPLEX does not return the "true" optimal solution to the problem. When I manually fix some binaries, I can increase the objective value (without breaking any constraints) by more than 1%. I'm sure that this is caused by a mis...
- 1 year ago
- Forum: Modeling
- Topic: Generate Equation and Column Listing without solving
- Replies: 3
- Views: 571
Re: Generate Equation and Column Listing without solving
Hi,
Thanks a lot for that great hint Fred!
I just tried and it seems to work really nice
Best,
Christoph
Thanks a lot for that great hint Fred!
I just tried and it seems to work really nice

Best,
Christoph
- 1 year ago
- Forum: Modeling
- Topic: Generate Equation and Column Listing without solving
- Replies: 3
- Views: 571
Generate Equation and Column Listing without solving
Dear all, I would like to know if there is a way to generate the equation and column listing of a model without actually solving it (basically dry running the model). The background is that solving the model takes quiet some time, and for debugging I sometimes just want to check if e.g. the dollar c...
- 1 year ago
- Forum: Tools
- Topic: Atom GAMS IDE
- Replies: 0
- Views: 1353
Atom GAMS IDE
Hi, I worked on a GAMS IDE plugin for the popular Atom editor for the past half-year and thought that it might be of interest for some of you. The plugin is called linter-gams . Atom is an open-source editor maintained by Github, that features a beautiful user-interface, high customizability and a l...
- 1 year ago
- Forum: Syntax
- Topic: Domain checking in sameas (and similar commands)
- Replies: 0
- Views: 473
Domain checking in sameas (and similar commands)
As so often when writing code, typos happen. When such a typo occurs in a dollar conditional (in my case today using a sameas operator), and the typo happens to be part of the universal set already (because the typo is a set element from a different set), the GAMS compiler doesn't throw an error. Co...
- 1 year ago
- Forum: Modeling
- Topic: Dimension different in GAMS error message
- Replies: 2
- Views: 547
Re: Dimension different in GAMS error message
You could add a variable where you sum over the countries, but just make it sum over the Netherlands. Then you minimize that variable. I attached a file where I made the appropriate changes to your model.
- 1 year ago
- Forum: Announcements
- Topic: GAMS Studio
- Replies: 3
- Views: 3438
Re: GAMS Studio
I don't know whether this is the right forum for feedback, so please feel free to move/delete if deemed inappropriate. As I understood correctly, GAMS Studio is supposed to be an Open-Source project. If you are still in an early development phase, something really great for the Open-Source community...