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Hi sum(j$(ord(j) q), sum(s$(ord(s) < pp(j)-1), ... I am not sure if you really need to have s defined as a set based on pp(j). If you define s over all possible intervals and use the $-conditions in the summation, all should be fine. However, you could also use an explicit mapping (look for mapping ...

Hi Judith If Gams tells you something is zero, you better believe it and you should using display statements to check your code. A quick check (display TOTO) reveals that TOTO has a value of zero. If you look in your gdx file, TOTO is empty. Now, if I look at your gdxxrw command to read your data, y...

Just try it out

Hi
You can use the dollar sign to restrict the summation:

Code: Select all

sum((i,j,k)$r(j,k), ...

If this is not what you are looking for, please send your code with the summation, parameter and the sets defined, even if it doesn't work, so it is easier for us to help you.
Cheers
Renger

Hi Lucas

You could introduce an if condition using the time used from your two models:

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parameter totaltime 'Total time used';
model mymodel /all/;
solve...
totaltime = mymodel.resusd;

solve...
totaltime = totaltime + mymodel.resusd;

if(totaltime < 3600,
    solve mymodel
);

Cheers
Renger

Hi Baud Gams tells you exactly what is wrong with your code: In the case of the error 625 XSO(j) = Baud("Total Ligne",j); **** $148 148 Dimension different - The symbol is referenced with more/less indices as declared Gams puts the $148 below Baud. If you go up in your code, you will find ...

Hi You are trying to find the minimum of the variable ETA which is defined over the set i using an optimization approach. In your case, you could just find the minimum of sum(t,p_pvf(i,t)*c_pv(i)): parameter mymin ; mymin = smin(i, sum(t,p_pvf(i,t)*c_pv(i))); In your formulation you have a i objecti...

Hi
The extension "py" stands for a script in Python (see the documentation on using Python in Gams code).
You can use macros, but they are not as powerful as using python code.
Cheers
Renger

Hi ToSan

THis would probably be the constraint you are looking for:

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OnlyOneI(i)..
    sum(s, akt(i,s)) =l= 1;

At every i there can only be one or zero plants.

Cheers
Renger

Hi In equation 5 you defined your equation over c(nd,nd): these are only the diagonal elements (which are not part of the mapping). Use c(nd,nf) and the equation appears. This is probably due to the confusion resulting from the definition of a parameter, set, variable over a double index of the same...

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