Search found 23 matches

by Luca
1 month ago
Forum: Solvers
Topic: Solver stop conditions
Replies: 1
Views: 351

Solver stop conditions

Dear all,

I am using BARON + GAMS to solve a MINLP problem. I would like to stop the solver if the objective function does not change for a given interval of time or number of iterations. How can I do?

Thanks very much. Best,
Luca
by Luca
4 months ago
Forum: Syntax
Topic: retrieve the lower bound
Replies: 1
Views: 190

retrieve the lower bound

Dear all,

I am solving a model with baron through gams. I would like to retrieve the lower bound and the upper bound of the objective function obj.
There is a variable where the LB is saved: I image that obj.l return the upper bound.

Thanks in advance. Best regards,
Luca
by Luca
7 months ago
Forum: Syntax
Topic: Matrix multiplication in GAMS
Replies: 1
Views: 344

Matrix multiplication in GAMS

Dear all,

what is the best way to multiply two matrix in GAMS?

Thanks for all your answer,
Luca
by Luca
7 months ago
Forum: Syntax
Topic: GAMS CPU time
Replies: 4
Views: 413

Re: GAMS CPU time

usually I test code with single thread and I report this CPU time.
otherwise what you suggest to do ?

Thanks,
Luca
by Luca
7 months ago
Forum: Syntax
Topic: GAMS CPU time
Replies: 4
Views: 413

GAMS CPU time

Dear all,

I know in gams the elapsed time can be retrive by the couple of instructions:

scalar starttime; starttime = jnow;
....
scalar elapsed; elapsed = (jnow - starttime)*24*3600; display elapsed;

but how can i retrive the cpu time spent in gams by my code?

Thanks in advance,
Luca
by Luca
7 months ago
Forum: Tools
Topic: Gams and eigenvectors
Replies: 2
Views: 328

Re: Gams and eigenvectors

thanks very much. I will do the exercise
by Luca
7 months ago
Forum: Tools
Topic: Gams and eigenvectors
Replies: 2
Views: 328

Gams and eigenvectors

Dear all,

I am using the tool eigenvector.exe to compute the eigenvector of a matrix.
Gams return a matrix with the eigenvectors. Just one question: the eigenvector are the row or the column of that matrix?

Thanks very much. Best regards,
Luca
by Luca
10 months ago
Forum: Solvers
Topic: Infeasibilities in CPLEX
Replies: 2
Views: 2595

Re: Infeasibilities in CPLEX

Thanks very much for your help!

Luca
by Luca
10 months ago
Forum: Solvers
Topic: Infeasibilities in CPLEX
Replies: 2
Views: 2595

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
11 months ago
Forum: Modeling
Topic: Principal component analysis in GAMS
Replies: 1
Views: 1650

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