Search found 373 matches
- 3 weeks ago
- Forum: Modeling
- Topic: Zero Division Error
- Replies: 1
- Views: 831
Re: Zero Division Error
Hi Merey, Running your code, I get --- MOZSAM_test.gms(165) 4 Mb[FIL:"C:\Users\ffian\Documents\support\MOZSAM_test.gms",165,0] *** Error at line 165: division by zero (0)[LST:522] --- MOZSAM_test.gms(171) 4 Mb 1 Error[FIL:"C:\Users\ffian\Documents\support\MOZSAM_test.gms",171,0] ...
- 2 months ago
- Forum: Syntax
- Topic: GAMS/CPLEX Model Creation Time
- Replies: 3
- Views: 2696
Re: GAMS/CPLEX Model Creation Time
Hi Gabriel, Adam already shared a link to some hints on how to formulate a model efficiently. If this did not help, I suggest you share your code and data, such that other forum user can analyze and provide help. If this cannot be shared publicly (e.g. due to confidentiality), feel free to reach out...
- 2 months ago
- Forum: Modeling
- Topic: How can I get very old GAMS version?
- Replies: 1
- Views: 2302
- 2 months ago
- Forum: Modeling
- Topic: Performance Difference between LP and MIP with fixed integer variables
- Replies: 1
- Views: 3466
Re: Performance Difference between LP and MIP with fixed integer variables
Usually, there shouldn't be a big difference in performance. But I guess in some corner cases solver behavior might be different. Fixing a variable means setting upper and lower bound to the same value. But it is still a variable and feasibility and integrality may be violated within the tolerances....
Re: error 198
I guess you are running into a problem with an unordered set. Looking at this example may help.
When sharing code, please use code tags or attach a gms file. Just pasting code as text breaks the alignment which is especially annoying when using table statements.
I hope this helps!
Fred
When sharing code, please use code tags or attach a gms file. Just pasting code as text breaks the alignment which is especially annoying when using table statements.
I hope this helps!
Fred
- 2 months ago
- Forum: Modeling
- Topic: Binary variable to count other variable within model
- Replies: 1
- Views: 2605
Re: Binary variable to count other variable within model
Hi, It would be easier to help, if you could share the files requored to run your code. Just from looking at it, it is quite challenging to say why the model is integer infeasible without having access to the date that goes into the model. On a side note, constraints like eq_ELECTROLYSER_Trans1(E).....
- 2 months ago
- Forum: Modeling
- Topic: Need for help
- Replies: 3
- Views: 2421
Re: Need for help
Hi, Then I do not understand the model. Look for example at free variable d1. It occurs with coefficient 1 in the objective which is minimized. Other than that it occurs only in constraint "Tracking", also with coefficient 1. This is a "=L=" constraint. So the solver will make d1...
- 2 months ago
- Forum: Syntax
- Topic: gdxxrw error 343 in
- Replies: 4
- Views: 2067
Re: gdxxrw error 343 in
Hi,
I cannot reproduce the issue mentioned in the initial post. Please note that Excel has to be installed and activated for gdxxrw to work.
I hope this helps!
Fred
I cannot reproduce the issue mentioned in the initial post. Please note that Excel has to be installed and activated for gdxxrw to work.
I hope this helps!
Fred
- 2 months ago
- Forum: Modeling
- Topic: How do I formulate logical expressions in equations with variables??
- Replies: 4
- Views: 3779
- 3 months ago
- Forum: Modeling
- Topic: Need for help
- Replies: 3
- Views: 2421
Re: Need for help
It seems that your model is unbounded. You might want to set proper lower bounds on variables d1,d2,d3,d4.
I hope this helps.
Fred
I hope this helps.
Fred