Search found 17 matches
- 3 years ago
- Forum: Modeling
- Topic: How to interpret BARON solutions
- Replies: 2
- Views: 3050
Re: How to interpret BARON solutions
Thank you very much Michael.
- 3 years ago
- Forum: Modeling
- Topic: How to interpret BARON solutions
- Replies: 2
- Views: 3050
How to interpret BARON solutions
Hi Everyone,
I solved my nlp model using BARON and got two different solutions, feasible and the best possible, please refer to below screenshot: Among these two solutions, which one of them is the Global Optimal Solution?
Thanks
zar
I solved my nlp model using BARON and got two different solutions, feasible and the best possible, please refer to below screenshot: Among these two solutions, which one of them is the Global Optimal Solution?
Thanks
zar
- 3 years ago
- Forum: Modeling
- Topic: Can the value of Big M change my results?
- Replies: 2
- Views: 2091
Re: Can the value of Big M change my results?
Hi,
As per literature, you can use below equation in your model to find out value of bigM:
bigM = (x.UP - x.LO)*(y.UP - y.LO)
Regards,
ZAR
As per literature, you can use below equation in your model to find out value of bigM:
bigM = (x.UP - x.LO)*(y.UP - y.LO)
Regards,
ZAR
- 3 years ago
- Forum: Modeling
- Topic: Conditional variables
- Replies: 4
- Views: 3497
Re: Conditional variables
Hi Fred,
Can you help me with formulating the following function: where, a(n) and a(n+1) are parameters, x and lambda(n) are variables.
Appreciate your help.
Thanks,
zar
Can you help me with formulating the following function: where, a(n) and a(n+1) are parameters, x and lambda(n) are variables.
Appreciate your help.
Thanks,
zar
- 3 years ago
- Forum: Modeling
- Topic: Linearisation of Bilinear Terms Using McCormick Envelopes
- Replies: 1
- Views: 2594
Linearisation of Bilinear Terms Using McCormick Envelopes
Hi Everyone, I am solving a problem by linearizing bilinear terms using McCormick envelopes. *NOTE: Equations are not written exactly as per standard GAMS syntex, so please ignore that and get the idea. *I want to linearize the following biliear term (EQ 1) using McCormick Envelopes: VARIABLES q, st...
- 3 years ago
- Forum: Modeling
- Topic: Using solution of one model as upper/lower bound in that model again - Global Optimization
- Replies: 1
- Views: 1557
Using solution of one model as upper/lower bound in that model again - Global Optimization
Hi everyone, I working on a global optimization problem, where I want to improve solution search space of the algorithm by using solution of local NLP solver as an upper/lower bound in the relaxed version of that model again. How can I achieve that: (a) By defining both models in the same file i.e a...
- 4 years ago
- Forum: Syntax
- Topic: Using Loop on Objective Function when the Looping Index is also Domain of a Table
- Replies: 8
- Views: 13091
Re: Using Loop on Objective Function when the Looping Index is also Domain of a Table
Hi Renger,
Thank you for your elaborate response. My problem is finally solved.
I owe you a Coca Cola
ZAR
Thank you for your elaborate response. My problem is finally solved.
I owe you a Coca Cola
ZAR
- 4 years ago
- Forum: Syntax
- Topic: Using Loop on Objective Function when the Looping Index is also Domain of a Table
- Replies: 8
- Views: 13091
Re: Using Loop on Objective Function when the Looping Index is also Domain of a Table
Hi Renger, I appreciate your replies. Now, I defined my model parameters as below: PARAMETERS M 'Operating Mode' /A, B, C/ ratiomodel(p) / GO.A 0.1117 GO.B 0.1172 GO.C 0.1173 HN.A 0.0946 HN.B 0.0279 HN.C 0.0279 /; In the Loop, I defined the code as: LOOP(m, ratiomodel(p) = ratio(p,m); When I execute...
- 4 years ago
- Forum: Syntax
- Topic: Problem maximizing a infeasible function
- Replies: 4
- Views: 2943
Re: Problem maximizing a infeasible function
Hi,
According to my experience, this happens when there is a problem with model formulation. You may check the constraints and objective function.
Regards,
According to my experience, this happens when there is a problem with model formulation. You may check the constraints and objective function.
Regards,
- 4 years ago
- Forum: Syntax
- Topic: Using Loop on Objective Function when the Looping Index is also Domain of a Table
- Replies: 8
- Views: 13091
Re: Using Loop on Objective Function when the Looping Index is also Domain of a Table
Hi Ranger, Thank you for your feedback. Are you suggesting to drop looping index(m) from the table as well? In the existing case, the table is 2-dimensional having looping index (m) on x-axis and liquid fractions (p) on y-axis. If I remove 'm' from the table then there will be a domain violation. Re...