Solve and optimize in loop

[hh....@lycos.com]

Hello all,

I am a beginner, trying to write this in GAMS.
I have a set t(time) and other sets and I want to calculate something that is growing over time.
p(0) (p at t = 0) is the initial value.
X is the growing factor, a constant.
O(a,b) is a variables that needs to be optimized over time period, a and b is set names
So I wrote something like:

//the empty lines contains  model
//.................................................
//.................................................
model mymodel/ALL;
loop(t,
        solve problem maximizing my objective function;     // to get O(a,b) and other variables
        p(t) = (1+X) * p(t-1) - O(a,b,t-1);
);

I know how to do this in C/C++ with while do loop or for loop, but I am not familiar yet with GAMS syntax.
Thanks.

regards,
sungai.

[Nikit Abhyankar]

You cannot put solve statement or equations in the loop statements.

So, take the solve statement out of the loop and it should work. 

--
You received this message because you are subscribed to the Google Groups "gamsworld" group.
To post to this group, send email to gams...@googlegroups.com.
To unsubscribe from this group, send email to gamsworld+...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/gamsworld?hl=en.

[Steven Dirkse]

Sungai,

You should have a look at the models in the GAMS model library. For
example, the model icut has a solve within a loop, etc.

-Steve

> --
> You received this message because you are subscribed to the Google Groups
> "gamsworld" group.
> To post to this group, send email to gams...@googlegroups.com.
> To unsubscribe from this group, send email to
> gamsworld+...@googlegroups.com.
> For more options, visit this group at
> http://groups.google.com/group/gamsworld?hl=en.
>

--
Steven Dirkse, Ph.D.
GAMS Development Corp.,  Washington DC
Voice: (202)342-0180     Fax: (202)342-0181
sdi...@gams.com
http://www.gams.com

[hh....@lycos.com]

Thanks for your insight.
My solution shouldn't be integers. And to change it to MIP model could be painful for me.
Does icut also cover non MIP?

regards,
sungai.

[hh....@lycos.com]

Thanks for your insight.
My solution shouldn't be integers. And to change it to MIP model could be painful for me.

However, it is intended to be an equilibrium model.

[hh....@lycos.com]

Another thing, it is supposed to be an equilibrium model
Thanks. Sorry for double message.

regards,
sungai.