Search found 214 matches
- 1 year ago
- Forum: Solvers
- Topic: CONOPT4 and MOSEK option files
- Replies: 12
- Views: 9590
Re: CONOPT4 and MOSEK option files
Fermar, You did not include your model, or any sort of GAMS code to use to reproduce your results, so it's difficult to say exactly what is needed. Looking at your CONOPT options, the most striking thing to me is that you have * Maximum and minimum jacobian element rtmaxj = 1.00e+20 * internal value...
- 1 year ago
- Forum: Modeling
- Topic: Loop Function and Parameters Based on a Distribution
- Replies: 6
- Views: 1874
Re: Loop Function and Parameters Based on a Distribution
Diabolik, Sometimes it is useful to simply put your eyes on the data. In this case, to display and look at the c(j) and d(j) values in each pass of the loop. My guess is that you'll see the d(j) filling up or becoming less sparse. The assignment d(j)$onoff(j) = uniform(20,200); does the expected thi...
- 1 year ago
- Forum: Modeling
- Topic: Loop Function and Parameters Based on a Distribution
- Replies: 6
- Views: 1874
Re: Loop Function and Parameters Based on a Distribution
Hello,
Perhaps this is what you are looking for.
-Steve
Perhaps this is what you are looking for.
-Steve
Code: Select all
execseed = 86358;
set j / 1 * 20 /;
scalar offProb / 0.8 /;
parameters d(j), onoff(j);
onoff(j) = uniform(0,1);
onoff(j) = 1$[onoff(j) >= offProb];
d(j)$onoff(j) = uniform(20,200);
display onoff, d;
- 1 year ago
- Forum: Modeling
- Topic: positive mathematical programming
- Replies: 1
- Views: 971
Re: positive mathematical programming
Hello,
Marginal values are frequently negative. If we exclude the zero marginal values, I suppose marginals are negative about half the time.
Why do you find it surprising that your marginals are negative?
-Steve
Marginal values are frequently negative. If we exclude the zero marginal values, I suppose marginals are negative about half the time.
Why do you find it surprising that your marginals are negative?
-Steve
- 1 year ago
- Forum: Solvers
- Topic: Equation Listing for nonlinear eqs
- Replies: 3
- Views: 2529
Re: Equation Listing for nonlinear eqs
Hi, I think you understand the mathematical/numerical content that is there when a nonlinear equation is shown in the listing file. It seems you are not on the same page about the particular form used to convey this information; perhaps I can help explain how this evolved. For simplicity, I just use...
- 1 year ago
- Forum: Solvers
- Topic: How to change path solver option during execution
- Replies: 1
- Views: 1690
Re: How to change path solver option during execution
Hello,
You can write the options file path.opt during GAMS execution via the put facility:
https://www.gams.com/40/docs/UG_Put.html
-Steve
You can write the options file path.opt during GAMS execution via the put facility:
https://www.gams.com/40/docs/UG_Put.html
-Steve
- 1 year ago
- Forum: API
- Topic: GAMS parameter initialisation as Modifier in Python GAMSModelInstance
- Replies: 2
- Views: 4617
Re: GAMS parameter initialisation as Modifier in Python GAMSModelInstance
Of course, if you are sending the MRE (Min Reproducible Example), you should also send the .log and .lst files from your run that exhibits the error.
-Steve
-Steve
- 1 year ago
- Forum: API
- Topic: GAMS parameter initialisation as Modifier in Python GAMSModelInstance
- Replies: 2
- Views: 4617
Re: GAMS parameter initialisation as Modifier in Python GAMSModelInstance
Hi, This sounds like an interesting problem. If you can provide a minimal sort of example that reproduces this, it seems likely I can provide some useful feedback. As an example, have a look at the obstacle example in the GAMS model library: https://www.gams.com/40/gamslib_ml/libhtml/gamslib_obstacl...
- 1 year ago
- Forum: Syntax
- Topic: Subset of multiple subsets
- Replies: 4
- Views: 6477
Re: Subset of multiple subsets
Martin, The situation you describe has appeared in practice a few times, but fortunately not so often. I usually take the approach of declaring subsets, parameters and variables over the larger set, like this: sets abc /a, b, c/ ab[abc] /a, b/ a[abc] /a/ ac[abc] /a, c/ c[abc] /c/ ; parameter foo[abc...
- 1 year ago
- Forum: Modeling
- Topic: Equality constraint not enforced
- Replies: 4
- Views: 5456
Re: Equality constraint not enforced
Zack, Yes, the log shows that your models are solved properly. I suggest you contact GAMS directly via support@gams.com (or with a phone call) to pursue this matter. It's possible we may need a reproducible example that we can run here in order to resolve this issue. If you can provide that easily, ...