Search found 7 matches
- 1 year ago
- Forum: Modeling
- Topic: including non-linearies in the objective function
- Replies: 0
- Views: 2336
including non-linearies in the objective function
Is there any advantage of including all the non-linearities of a model in the objective function compared to writing the non-linearities as individual constraints? Let me clarify that with a fictitious example: Let us consider we want to minimise the area of a circle, so our decision variable is the...
- 3 years ago
- Forum: Modeling
- Topic: why does the solver give the best found solution when it already knows the best possible solution?
- Replies: 2
- Views: 2747
Re: why does the solver give the best found solution when it already knows the best possible solution?
Thank you very much, Michael.
It helped me a lot. I could get so many other things that I had been struggling with.
Best regards.
It helped me a lot. I could get so many other things that I had been struggling with.
Best regards.
- 3 years ago
- Forum: Modeling
- Topic: why does the solver give the best found solution when it already knows the best possible solution?
- Replies: 2
- Views: 2747
why does the solver give the best found solution when it already knows the best possible solution?
Hi everyone. When solving a MIP sometimes the solver gives two solutions namely the Best Found (BF) and the Best Possible (BP). Why does the solver (using CPLEX) give the Best Found when it already knows the Best Possible? Is the reason because it is extremely difficult to solve and takes "enor...
- 3 years ago
- Forum: Modeling
- Topic: solver solution differs from the best solution - PART 2
- Replies: 2
- Views: 2907
Re: solver solution differs from the best solution - PART 2
You helped me a lot.
I provided the solution by hand and the result was infeasible. The log showed what specifically was infeasible and then I could find out the mistake I had made during the code development.
I wish you the very best, thank you so much.
I provided the solution by hand and the result was infeasible. The log showed what specifically was infeasible and then I could find out the mistake I had made during the code development.
I wish you the very best, thank you so much.
- 3 years ago
- Forum: Modeling
- Topic: solver solution differs from the best solution - PART 2
- Replies: 2
- Views: 2907
solver solution differs from the best solution - PART 2
Hello everyone, I'm modelling a MIP. The solver is oriented to minimise the objective function. I know that the best solution of the MIP is 43,8 (I've solved it by hands). When I ran GAMS, the solver (CPLEX) did not reach the best value, as you guys can see: Solution satisfies tolerances. MIP Soluti...
- 3 years ago
- Forum: Modeling
- Topic: solver solution differs from the best solution
- Replies: 2
- Views: 2628
Re: solver solution differs from the best solution
you did great!
thank you so much
thank you so much
- 3 years ago
- Forum: Modeling
- Topic: solver solution differs from the best solution
- Replies: 2
- Views: 2628
solver solution differs from the best solution
Hello everybody, I have used MIP to solve a model. GAMS log showed the following: Solution satisfies tolerances. MIP Solution: 46.800000 (245 iterations, 17 nodes) Final Solve: 46.800000 (18 iterations) Best possible: 43.800000 Absolute gap: 3.000000 Relative gap: 0.064103 Could anyone here point ou...