Search found 1037 matches
- 4 months ago
- Forum: Syntax
- Topic: GAMSpy error
- Replies: 1
- Views: 7847
Re: GAMSpy error
I fear your screen shot is not enough to point you to the issue. Please share the entire Python script (or make a minimal example) so one can reproduce. If you are a licensed user and can't share the script here in the forum, you might want to consider to email support@gams.com with something that l...
- 4 months ago
- Forum: Tools
- Topic: Excel export and import in a loop
- Replies: 2
- Views: 7720
Re: Excel export and import in a loop
One issue might be, that Connect's Excel reader reads values from the spreadsheet. It does not reevaluate formulas. So if you write to one part of the spreadsheet and hope that another part gets recalculated, I think this is not happening. The Excel API we use in Connect just does not do that. For t...
- 4 months ago
- Forum: Modeling
- Topic: Tuning CPLEX solver options for large-scale MIP problems
- Replies: 4
- Views: 13107
Re: Tuning CPLEX solver options for large-scale MIP problems
When switching from one version to another, I always give "default" a try (you can copy the tolerance options, e.g. epgap etc) but no algorithmic option and see how the solver does. If that's no good, then I would go for the meta options (e.g. mipemphasis) and depending on some experiments...
- 5 months ago
- Forum: Announcements
- Topic: Introducing GAMSPy
- Replies: 0
- Views: 21123
Introducing GAMSPy
Exciting Announcement: We are introducing GAMSPy! What is GAMSPy? GAMSPy combines the high-performance GAMS execution system with the flexible Python language, creating a powerful mathematical optimization package. It acts as a bridge between the expressive Python language and the robust GAMS system...
- 5 months ago
- Forum: Syntax
- Topic: Option Threads = 8
- Replies: 4
- Views: 10966
Re: Option Threads = 8
Where did you read about "option threads=n"? Probably in a much newer GAMS documentation. Software evolves. Your version of GAMS is 13 years old! If you use that old software use the documentation that came with that version. At that time, there was no general GAMS option "threads&quo...
- 6 months ago
- Forum: Announcements
- Topic: GAMS Distribution 45.1.0 (Major Release)
- Replies: 0
- Views: 22188
GAMS Distribution 45.1.0 (Major Release)
Hi GAMS Users,
We started distributing GAMS Release 45.1.0 on October 17, 2023.
You can download the software from https://www.gams.com/download/
Here are the release notes: https://www.gams.com/latest/docs/RN_45.html
Your GAMS Team
www.gams.com
We started distributing GAMS Release 45.1.0 on October 17, 2023.
You can download the software from https://www.gams.com/download/
Here are the release notes: https://www.gams.com/latest/docs/RN_45.html
Your GAMS Team
www.gams.com
- 6 months ago
- Forum: Announcements
- Topic: GAMS Distribution 45.0.0 (Beta Release)
- Replies: 0
- Views: 20162
GAMS Distribution 45.0.0 (Beta Release)
Hi GAMS Users, We would like to announce the availability of the GAMS Beta Release 45.0.0. Please consult the beta release notes for details about new features and updated solvers: https://www.gams.com/beta/docs/RN_45.html If you are interested in experimenting with this beta release, please downloa...
- 6 months ago
- Forum: Modeling
- Topic: define new equation in each loop iteration
- Replies: 3
- Views: 9471
Re: define new equation in each loop iteration
There is a somewhat simpler example: cta (https://www.gams.com/latest/gamslib_ml/ ... b_cta.html) which essentially cuts away the optimal solution a couple of time to get suboptimal solutions. -Michael
- 6 months ago
- Forum: Modeling
- Topic: define new equation in each loop iteration
- Replies: 3
- Views: 9471
Re: define new equation in each loop iteration
Look at a TSP example (https://www.gams.com/latest/gamslib_ml/ ... _tsp1.html) in the GAMS model library where a sub-tour elimination constraint gets added in every iteration. You will need to overestimate the number of iterations (cc) and use a loop though. Good luck.
-Michael
-Michael
- 6 months ago
- Forum: Solvers
- Topic: Baron License error
- Replies: 1
- Views: 6374
Re: Baron License error
The error message is slightly misleading, it probably failed because the model you want to solve is too big for the community license. See https://www.gams.com/latest/docs/UG_License.html#UG_License_Additional_Solver_Limits for the model size limits for the community license. BARON has tighter limit...