Search found 10 matches

by sam_Hab
11 months ago
Forum: Syntax
Topic: Urgent HELP! , GDX output in a loop uses old variable values
Replies: 7
Views: 1148

Urgent HELP! , GDX output in a loop uses old variable values

Hello everyone, I am trying to solve several problems in a loop and for each, I am generating the corresponding .gdx and .xlsx file Scalar product ; Scalar supplier ; Scalar time ; Sets i products / i0*i50 / j suppliers / j0*j50 / t time periods / t0*t50 / sub_j(j) dynamic subset for j sub_t(t) dyna...
by sam_Hab
1 year ago
Forum: Syntax
Topic: How to tune the parameter of CPLEX for solving large MIP problem
Replies: 1
Views: 790

How to tune the parameter of CPLEX for solving large MIP problem

Hello everyone, I want to know how to use CPLEX automatic tuning tool, I found the parameters to use https://www.gams.com/latest/docs/S_CPLEX.html#CPLEXtuningSHORTDOC, but I am not sure how to use them. I have tried the following code but I cannot find the output file for the parameters that CPLEX a...
by sam_Hab
1 year ago
Forum: Syntax
Topic: Add Heuristic to CPLEX Bender's decomposition under GAMS
Replies: 1
Views: 815

Add Heuristic to CPLEX Bender's decomposition under GAMS

I was wondering if there is a way to add a heuristic to CPLEX Bender's decomposition under GAMS and how to do it? I am using CPLEX Bender's decomposition: https://www.gams.com/latest/docs/S_CPLEX.html#CPLEXbendersstrategy Also, can BCH facility work with Bender's decomposition under CPLEX , BCH faci...
by sam_Hab
1 year ago
Forum: Modeling
Topic: Accelerate Bender's decomposition using CPLEX
Replies: 2
Views: 879

Re: Accelerate Bender's decomposition using CPLEX

Thanks a lot for your answer, I was wondering if there is a way to add a heuristic to Benders decomposition under GAMS and how to do it?
by sam_Hab
1 year ago
Forum: Modeling
Topic: Accelerate Bender's decomposition using CPLEX
Replies: 2
Views: 879

Accelerate Bender's decomposition using CPLEX

Hello everyone, I am trying to apply the benders decomposition using CPLEX (strategy 3), I want to know if I am doing it the right way because I only found one example using it. Here is the link https://www.gams.com/latest/gamslib_ml/libhtml/gamslib_cbenders.html Also, I want to know if there is an ...
by sam_Hab
1 year ago
Forum: Syntax
Topic: Produce .lst, .gdx and .xls for each solve statement
Replies: 3
Views: 563

Re: Produce .lst, .gdx and .xls for each solve statement

Hello,

Thanks for your answer, I was able to create a .gdx file and the corresponding .xls file for each solve statement but I am not able to produce a new .lst file for each solve statement. Do you have any suggestions?

Thanks
by sam_Hab
1 year ago
Forum: Syntax
Topic: Produce .lst, .gdx and .xls for each solve statement
Replies: 3
Views: 563

Produce .lst, .gdx and .xls for each solve statement

Hello everyone, I am trying to generate random problems using gams, solve them and then save the solutions into different Excel files, .lst files and .gdx files. I am trying to figure out how to change the file name and produce a .lst, .xls and .gdx files for each solve statement The code I have bel...
by sam_Hab
1 year ago
Forum: Syntax
Topic: Define dynamic set using embedded code facility
Replies: 4
Views: 618

Re: Define dynamic set using embedded code facility

Thank you so much, that worked :D
by sam_Hab
1 year ago
Forum: Syntax
Topic: Define dynamic set using embedded code facility
Replies: 4
Views: 618

Re: Define dynamic set using embedded code facility

Thanks for your quick response I included what you mentioned and I tested it and it is working pretty fine but in a way simpler than my code with the embedded facility code, however, I am still getting the same error with the dynamic set assignment for the objective function and the first constraint...
by sam_Hab
1 year ago
Forum: Syntax
Topic: Define dynamic set using embedded code facility
Replies: 4
Views: 618

Define dynamic set using embedded code facility

Hello , I am new to gams and I am trying to define a dynamic set in a "for statement". In fact, I want to solve my model using a different set each time and I am using the embedded code facility for python to define in each iteration my new dynamic set. In my model I have declared my parameters and ...