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by bussieck
1 week ago
Forum: Announcements
Topic: GAMS Distribution 30.1.0 Announcement
Replies: 0
Views: 45

GAMS Distribution 30.1.0 Announcement

Hi GAMS Users,

We started distributing GAMS Release 30.1.0 on January 10. 2020.

You can download the software from https://www.gams.com/download/.

Here are the release notes: https://www.gams.com/latest/docs/RN_30.html

Your GAMS Team
www.gams.com
by bussieck
3 weeks ago
Forum: Modeling
Topic: Exit code 3
Replies: 1
Views: 171

Re: Exit code 3

Seriously? You post a picture from a log with a stolen license and expect help?

-Michael
by bussieck
3 weeks ago
Forum: Syntax
Topic: Reading in Large Tables
Replies: 1
Views: 119

Re: Reading in Large Tables

No, This looks more like a syntax problem. If you post something that lets us reproduce the issue or you paste some actual log output together with the commands you issue, that would help us helping you.

-Michael
by bussieck
3 weeks ago
Forum: Syntax
Topic: Error 2- Identifier Expected
Replies: 13
Views: 538

Re: Error 2- Identifier Expected

If you have a scenario loop you need to move all the declarations and equation definitions before this loop. Also check your understanding of compile and execution time in GAMS. Multiple "$echo deltaterm 1 > baron.opt" have no effect because they are all done before execution starts, so the last "$e...
by bussieck
4 weeks ago
Forum: Syntax
Topic: Error 149 uncontrolled set entered as constant
Replies: 1
Views: 140

Re: Error 149 uncontrolled set entered as constant

Your equation is controlled by i only. Your right hand side has a symbol (qiBiZhangtai) indexed by i and t. What t?

-Michael
by bussieck
4 weeks ago
Forum: Syntax
Topic: Error 2- Identifier Expected
Replies: 13
Views: 538

Re: Error 2- Identifier Expected

Just make 5 models and solve them in sequence. Check the model/solve status if you have a feasible solution: e11.. 1/Te*log((W*Te/D)+1) =L= M-N; e12.. T =G= M-N; o1.. z1 =E= A/T+(h*D)/(sqr(Te)*T)*((exp(Te*T)-1)-(Te*T))+(c/T)*((D/Te)*(exp(Te*T)-1)-D*T)+((c*Ip*D)/T)*((sqr(T+N-M))/2)-((p*Ie*D)/T)*((sqr...
by bussieck
1 month ago
Forum: Modeling
Topic: Infeasible solution
Replies: 1
Views: 234

Re: Infeasible solution

What I usually do in such a situation, I try to get hold of a feasible solution (perhaps one is reported in the paper or you find a trivial one). Now you initialize all your variables *before* the solve statement to this reported solution. Next, you turn on the equation listing (modelname.limrow=1e9...
by bussieck
1 month ago
Forum: Modeling
Topic: How can I do this in GAMS?
Replies: 1
Views: 144

Re: How can I do this in GAMS?

This is very tricky and would require more effort (and lots of binary variables) than just modeling "t from D" directly. So why not model "t from D" directly, is it possible to have a t not in D in an optimal solution? Integer variable di; di.lo=1 di.up=6; variable t; equation deft; deft.. t =e= 0.2...
by bussieck
1 month ago
Forum: Syntax
Topic: Error 2- Identifier Expected
Replies: 13
Views: 538

Re: Error 2- Identifier Expected

Use a lower bound on T (T.lo=1e-3;) Also don't use **2 for squares. ** is the real power operator. If you have **2, use sqr which can have negative arguments, while **2 cannot.

-Michael
by bussieck
1 month ago
Forum: Syntax
Topic: Error 2- Identifier Expected
Replies: 13
Views: 538

Re: Error 2- Identifier Expected

Terminate your statements with a ';' then you are on the safe side. There are plenty more errors... Parameters input(scenario,*) Input for the scenarios, report(scenario,*) Reporting Results(*,scenario) Saving results D the annual demand rate, A the ordering cost per order, W The supplier's predefin...