Search found 16 matches

by Luca
1 month ago
Forum: Solvers
Topic: Infeasibilities in CPLEX
Replies: 2
Views: 2221

Re: Infeasibilities in CPLEX

Thanks very much for your help!

Luca
by Luca
1 month ago
Forum: Solvers
Topic: Infeasibilities in CPLEX
Replies: 2
Views: 2221

Infeasibilities in CPLEX

Dear all, I am programming in GAMS using CPLEX as MIP solver. I activated the following options for CPLEX feasopt 1 numericalemphasis 1 scaind 1 CPLEX should provide the "less infeasible" solution to the problem. However I obtain the following error: Feasible solution. ------------------------------...
by Luca
1 month ago
Forum: Modeling
Topic: Principal component analysis in GAMS
Replies: 1
Views: 1402

Principal component analysis in GAMS

Dear all,
I would like to implement principal component analysis in GAMS. I would ask you if there are linear algebra facilities in GAMS (such as tools to compute eigenvalues...) or there are libraries already available for PCA in GAMS.

Thanks very much for your help. Best regards,
Luca
by Luca
2 months ago
Forum: Syntax
Topic: Excel printing problem
Replies: 3
Views: 1057

Re: Excel printing problem

Thanks very much. Now it works.
Best regards,
Luca
by Luca
2 months ago
Forum: Syntax
Topic: Excel printing problem
Replies: 3
Views: 1057

Excel printing problem

Dear all users,

I am using GAMS to solve an optimisation problem and I am printing the results to an excel sheet. I wold ask you if there is a way to print in excel all the entries of a variable included the zero entries.

Thanks in advance. Best regards,
Luca
by Luca
2 months ago
Forum: Syntax
Topic: Problem in changing the parameter.
Replies: 6
Views: 737

Re: Problem in changing the parameter.

Thanks for the answer. I have already check the difference between fsSOL matrix and apparently all is ok.
But, when I solve the problems (which apparently are the same), I obtain different solutions.
-- Luca
by Luca
2 months ago
Forum: Syntax
Topic: Problem in changing the parameter.
Replies: 6
Views: 737

Re: Problem in changing the parameter.

Here there is the code. I have a master problem, PROBLEM1, whose constraints are dynamically added by solving PROBLEM2. The syntax is correct, but the code has a strange behaviour (I am not sure I use the dynamic set in the right way). Thanks very much for all your suggestions.
by Luca
2 months ago
Forum: Syntax
Topic: Problem in changing the parameter.
Replies: 6
Views: 737

Re: Problem in changing the parameter.

Thanks very much for your answer. It is true that I have different value for the parameters, but the second equations are just the copy-paste of one of the equation in the first set. I have all the equation I need in the first group of constraints, while in the second one I have always a constraint ...
by Luca
2 months ago
Forum: Syntax
Topic: Problem in changing the parameter.
Replies: 6
Views: 737

Problem in changing the parameter.

Dear all, I am implementing a kind of branch and cut in GAMS and I have the following problem. I have a simple problem with just two nonnegative constaints in my model: set p auxiliary superset /1*200/ ; set i another set /1*100/ variables w(j,m) ; parameters fs1(j,i), fs2(j,p) ; equations contraint...
by Luca
4 months ago
Forum: Syntax
Topic: Semi-infinite Programs in GAMS
Replies: 1
Views: 197

Re: Semi-infinite Programs in GAMS

Now it is ok. It was my fault.

Sorry,
Luca