Hi,
I am building an economic model in GAMS, which, differently from the famous "transport" model does not call for optimization using lp or others. Usually, I just press f9 and GAMS runs it.
However, I have reached a phase where I will:
1) export some tables to R (I am using an Excel file as intermediate cause I have not found out how to send it directly to R - but it does not matter now),
2) run some analysis In R, and
3) Import it back to GAMS to continue the model
I wrote (in the body of the model) the gdx routine to export the files to Excel and it worked well. The import routine, however, I wrote in a separate file (also works well). When I tried to put both routines in the same file (the one containing the original model), it didn't work as I would like.
What I want, is to divide my model into parts:
1) First, to run the model until the part where I export the tables
2) Then, to run the routine importing the tables back into GAMS
3) Finally, to run the rest of the model
How do I do that? Does the "solve model_name" works even for models that "are not optimizing" anything?
Thanks.
Cheers,
Running GAMS in phases Topic is solved
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Re: Running GAMS in phases
look at save and restart
plus perhaps the sleep command to give R time to run
plus perhaps the sleep command to give R time to run
Re: Running GAMS in phases
Hi,
There is a tendency to overuse the word "model" in this area. For example, a GAMS model can be:
There are many ways to arrange your GAMS code and language features to support this. In particular, you should look at calling a separate GAMS source file from within GAMS via the '$call' or 'execute' commands.
https://www.gams.com/latest/docs/UG_Dol ... _21_option
https://www.gams.com/latest/docs/UG_Gam ... larExecute
Also, two examples that will probably give you some ideas:
https://www.gams.com/31/testlib_ml/libh ... h=invert01
https://www.gams.com/31/datalib_ml/libh ... ch=invert1
In particular the last example shows in general how you can export some data from GAMS to R, do some work in R, and bring new data from R back to GAMS.
HTH,
Steve
There is a tendency to overuse the word "model" in this area. For example, a GAMS model can be:
- A bunch of GAMS code stored in a file.
- A GAMS symbol denoting a collection of equations, e.g.
Code: Select all
model m / all /;
There are many ways to arrange your GAMS code and language features to support this. In particular, you should look at calling a separate GAMS source file from within GAMS via the '$call' or 'execute' commands.
https://www.gams.com/latest/docs/UG_Dol ... _21_option
https://www.gams.com/latest/docs/UG_Gam ... larExecute
Also, two examples that will probably give you some ideas:
https://www.gams.com/31/testlib_ml/libh ... h=invert01
https://www.gams.com/31/datalib_ml/libh ... ch=invert1
In particular the last example shows in general how you can export some data from GAMS to R, do some work in R, and bring new data from R back to GAMS.
HTH,
Steve
Re: Running GAMS in phases
Thank you all for your replies.
After reading both suggestions and consulting GAMS documentation, I think brucemccarl's suggestion would fit my needs the best. The only problem is that I have an old version of GAMS (24.1) and apparently the save and restart does not work there. Am I right?
After reading both suggestions and consulting GAMS documentation, I think brucemccarl's suggestion would fit my needs the best. The only problem is that I have an old version of GAMS (24.1) and apparently the save and restart does not work there. Am I right?
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- User
- Posts: 13
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Re: Running GAMS in phases
save and restart has worked for decades
must be something else
must be something else