Search found 14 matches

by jshengdb
1 year ago
Forum: Solvers
Topic: How to change path solver option during execution
Replies: 1
Views: 1690

How to change path solver option during execution

Hi all, I am currently using path solver to solve a MCP and I need to use set the path.opt /proximal_perturbation SomeScalar/. My question is that I am running an interactive algorithm and each time I need to change 'SomeScalar' equal to a number that calculated during execution time. I am wondering...
by jshengdb
3 years ago
Forum: Modeling
Topic: Issume of MCP has empty equation
Replies: 0
Views: 1919

Issume of MCP has empty equation

Hello GAMS user, I have a wierd issue when I try to solve the Mixed Complementarity Problem. In short, the problem is that during execution, the system tells me that the defxDev in the model is 'None'. However, when I define the model, I define the equation as: defxDev(a).. -1 =N= 0; I don't know wh...
by jshengdb
3 years ago
Forum: Syntax
Topic: Data exchange: $gdxin works but execute_load fails
Replies: 1
Views: 1977

Data exchange: $gdxin works but execute_load fails

Hello GAMS users, I am trying to load set and parameter from a GDX file (subhessian.gdx) using the 'execute_load' command. For some reason it doesn't load the data and returns a 'zero' value for all the parameters. However, the strange thing is I am able to use '$gdxin' to load the set and parameter...
by jshengdb
4 years ago
Forum: Solvers
Topic: How to define the empinfo file dynamically
Replies: 1
Views: 2754

How to define the empinfo file dynamically

Hi everyone, Currently I am trying to use a decomposition method to solve a large-scale equilibrium problem, and at each iteration I am trying to solve a small equilibrium subproblem. The trick I use is that if the whole problem has a set m = /m1, m2, m3/, I can define a dynamic set mm(n), and each ...
by jshengdb
4 years ago
Forum: Tools
Topic: How to calculate the total solver resource usage time
Replies: 3
Views: 4895

Re: How to calculate the total solver resource usage time

bussieck wrote: 4 years ago Sorry, I meant mymodel.resUsd (not resLim). -Michael
Hi Michael,

Thanks for solving my problem. That's really helpful. I just have one more small question: I think the .resUsd and .etSolve will report the CPU time. Do you know how can I get the wall time from GAMS?

Thanks
by jshengdb
4 years ago
Forum: Syntax
Topic: Difference between 'equilibrium vi' and 'vi' in EMP
Replies: 1
Views: 2070

Difference between 'equilibrium vi' and 'vi' in EMP

Hi All,

I have a question between the difference between syntax 'equilibrium vi' and 'vi' in the EMP framework. Now I have a strongly monotone VI problem that can be solved by both syntax. However, the solution they give is quite different. I am just wondering what cause this situation.

Thanks
by jshengdb
4 years ago
Forum: Modeling
Topic: Too long execution time for a Dantzig-Wolfe decomposition method master problem
Replies: 2
Views: 2721

Re: Too long execution time for a Dantzig-Wolfe decomposition method master problem

Hi Fred, Thanks. This answer helps me a lot. Hi, You are comparing the execution time of a single solve approach (EMP) to your manual implementation of an iterative method (DW) where the second lst excerpt shows that the execution time of 131.764 SECONDS was reached at iteration 102. Hence, this exe...
by jshengdb
4 years ago
Forum: Tools
Topic: How to calculate the total solver resource usage time
Replies: 3
Views: 4895

How to calculate the total solver resource usage time

Hi All, I am now writing a iteration method to solve a optimization problem and now I have a question about how to calculate the total resource usage time spent by the solver. I know that when gams ends its execution, it will have a elapsed time to calculate the total time used by the program. But i...
by jshengdb
4 years ago
Forum: Modeling
Topic: Too long execution time for a Dantzig-Wolfe decomposition method master problem
Replies: 2
Views: 2721

Too long execution time for a Dantzig-Wolfe decomposition method master problem

Hi All, I'm now trying to solve a large Variational Inequality problem. And I solve it by two ways, using PATH solver solve it directly and use Dantzig-Wolfe method to solve it in a decomposition way. And when I implement the second way in GAMS, I found the time to solve it is relatively short, but ...
by jshengdb
5 years ago
Forum: Solvers
Topic: Strange problems about initial point of JAMS solver
Replies: 0
Views: 2139

Strange problems about initial point of JAMS solver

Dear All, I now have a very strange problems when use jams solver to solve a MOPEC problem. To solve my MOPEC, I will first solve a very similar system optimization problem to get a feasible initial point. (It is feasible since when I fix this initial point and solve the problem, the model status is...