Hi!

Because I'm getting the error 'OplRun is not responding, you must relaunch the RunConfig" (probably because my model is too big) I am looking at the Engine Log to see at least some of the solutions founded with an optimality gap.
I tried to run the model via the External Tools, but then my model run for more than a day and still did not found an optimal solution, so I stopped running the model.

Is it possible to see the corresponding decision variables with a solution from the Engine Log?
Or is it possible to save the Engine Log somewhere?

Thank you in advance!

------------------------------
Floor M
------------------------------

#DecisionOptimization

Yes, this is possible. See the chapter about postprocessing a feasible solution in the manual.

You can also look at running out of memory for strategies to avoid running out of memory.

There are also several limits you can set (time limit, solution limit, memory limit, ...). With such a limit set, CPLEX will stop gracefully in case the limit is hit and will return the best solution found so far.

------------------------------
Daniel Junglas
------------------------------

Hi Daniel,

Thank you for your quick response!

I ticked the box "Postprocess feasible solutions" at Language / Run as described in the manual you've sent. 
Do I need to add anything else to my codes? Like a postprocessing script in an execute statement to see my decision variables?

Thanks in advance!

------------------------------
Floor M
------------------------------

Original Message:
Sent: Fri June 05, 2020 10:14 AM
From: Daniel Junglas
Subject: Engine Log

Yes, this is possible. See the chapter about postprocessing a feasible solution in the manual.

You can also look at running out of memory for strategies to avoid running out of memory.

There are also several limits you can set (time limit, solution limit, memory limit, ...). With such a limit set, CPLEX will stop gracefully in case the limit is hit and will return the best solution found so far.

------------------------------
Daniel Junglas
------------------------------

Hi Daniel,

I am having some trouble displaying the decision variables..

I ticked the box "Postprocess feasible solutions" (as described in the comment before) and I added the following at the end of my model:
execute DISPLAY {
writeln("u[i][v][r]=", u[i][v][r] && "w[v][r]=", w[v][r]);
}

u[I][v][r] and w[v][r] are the decision variables I would like to see when I get a feasible solution.
I still get the error 'OplRun is not responding, you must relaunch the RunConfig" after some hours of running the model, and my scripting log remains empty. The engine log indicates that 10 solutions are found with different optimality gaps, but they won't display in the scripting log.
I tried to set a time limit, but cplex just runs over this time. 

I have read most of the manuals but I am still a little lost as you can see. 
It would be great if you could help me out!

------------------------------
Floor M
------------------------------

Original Message:
Sent: Fri June 05, 2020 10:14 AM
From: Daniel Junglas
Subject: Engine Log

Yes, this is possible. See the chapter about postprocessing a feasible solution in the manual.

You can also look at running out of memory for strategies to avoid running out of memory.

There are also several limits you can set (time limit, solution limit, memory limit, ...). With such a limit set, CPLEX will stop gracefully in case the limit is hit and will return the best solution found so far.

------------------------------
Daniel Junglas
------------------------------

That is strange. This works for me without any problem. Can you double-check that you added the .ops file to the run configuration?

I am attaching a working example of this feature (note that the example also adds a node limit since otherwise the solution process would run forever). Maybe this can help to figure out what you are missing.

------------------------------
Daniel Junglas
------------------------------

Original Message:
Sent: Sat June 06, 2020 10:07 AM
From: Floor M
Subject: Engine Log

Hi Daniel,

I am having some trouble displaying the decision variables..

I ticked the box "Postprocess feasible solutions" (as described in the comment before) and I added the following at the end of my model:
execute DISPLAY {
writeln("u[i][v][r]=", u[i][v][r] && "w[v][r]=", w[v][r]);
}

u[I][v][r] and w[v][r] are the decision variables I would like to see when I get a feasible solution.
I still get the error 'OplRun is not responding, you must relaunch the RunConfig" after some hours of running the model, and my scripting log remains empty. The engine log indicates that 10 solutions are found with different optimality gaps, but they won't display in the scripting log.
I tried to set a time limit, but cplex just runs over this time. 

I have read most of the manuals but I am still a little lost as you can see. 
It would be great if you could help me out!

------------------------------
Floor M
------------------------------


Original Message:
Sent: Fri June 05, 2020 10:14 AM
From: Daniel Junglas
Subject: Engine Log

Yes, this is possible. See the chapter about postprocessing a feasible solution in the manual.

You can also look at running out of memory for strategies to avoid running out of memory.

There are also several limits you can set (time limit, solution limit, memory limit, ...). With such a limit set, CPLEX will stop gracefully in case the limit is hit and will return the best solution found so far.

------------------------------
Daniel Junglas

It is working now, thank you so much for your help!

------------------------------
Floor M
------------------------------

Original Message:
Sent: Mon June 08, 2020 01:54 AM
From: Daniel Junglas
Subject: Engine Log

That is strange. This works for me without any problem. Can you double-check that you added the .ops file to the run configuration?

I am attaching a working example of this feature (note that the example also adds a node limit since otherwise the solution process would run forever). Maybe this can help to figure out what you are missing.

------------------------------
Daniel Junglas
------------------------------


Original Message:
Sent: Sat June 06, 2020 10:07 AM
From: Floor M
Subject: Engine Log

Hi Daniel,

I am having some trouble displaying the decision variables..

I ticked the box "Postprocess feasible solutions" (as described in the comment before) and I added the following at the end of my model:
execute DISPLAY {
writeln("u[i][v][r]=", u[i][v][r] && "w[v][r]=", w[v][r]);
}

u[I][v][r] and w[v][r] are the decision variables I would like to see when I get a feasible solution.
I still get the error 'OplRun is not responding, you must relaunch the RunConfig" after some hours of running the model, and my scripting log remains empty. The engine log indicates that 10 solutions are found with different optimality gaps, but they won't display in the scripting log.
I tried to set a time limit, but cplex just runs over this time. 

I have read most of the manuals but I am still a little lost as you can see. 
It would be great if you could help me out!

------------------------------
Floor M


Original Message:
Sent: Fri June 05, 2020 10:14 AM
From: Daniel Junglas
Subject: Engine Log

Yes, this is possible. See the chapter about postprocessing a feasible solution in the manual.

You can also look at running out of memory for strategies to avoid running out of memory.

There are also several limits you can set (time limit, solution limit, memory limit, ...). With such a limit set, CPLEX will stop gracefully in case the limit is hit and will return the best solution found so far.

------------------------------
Daniel Junglas