Search found 86 matches

by bussieck
6 minutes ago
Forum: API
Topic: model2tex
Replies: 1
Views: 8

Re: model2tex

Most likely your GAMS system is too old. Download the latest and greatest and try again.

-Michael
by bussieck
2 weeks ago
Forum: Modeling
Topic: Importing large csv files
Replies: 1
Views: 59

Re: Importing large csv files

Hi,

Have you tried csv2gdx (https://www.gams.com/latest/docs/T_CSV2GDX.html)? If that does not work I would be interested to take a closer look. Can you make the file available (or at least the first 100 or so rows)?

-Michael
by bussieck
2 weeks ago
Forum: Solvers
Topic: GAMS CPLEX Variable progress in log file
Replies: 3
Views: 110

Re: GAMS CPLEX Variable progress in log file

Tulio, The "points" in the iteration are *not* (necessarily) solutions. The log column "Prim Inf" tells you how infeasible the current point is. Anyhow, getting alternative solutions to an LP is a tricky questions, because there are an infinite number of them. So often people try to all basic soluti...
by bussieck
2 weeks ago
Forum: Solvers
Topic: GAMS CPLEX Variable progress in log file
Replies: 3
Views: 110

Re: GAMS CPLEX Variable progress in log file

There is no way to do that in GAMS/Cplex. There might be a barrier callback in the Cplex programming API to get called at every barrier iteration. But remember Cplex works on your presolved model and this variable space aggregates and eliminates variables. I think you are out of luck.

-Michael
by bussieck
3 weeks ago
Forum: Modeling
Topic: Sum of parameter
Replies: 1
Views: 89

Re: Sum of parameter

Hi, The parallel assignment statement does not work "in-place" or recursively. It makes a copy of the symbol on the left before it does the assignment. What you need is a loop: sets i 'temperature interval' /i0*i13/; parameters T(i) 'Length of interval i' / i0 0, i1 2, i2 6, i3 2, i4 8, i5 2, i6 4 i...
by bussieck
4 weeks ago
Forum: Syntax
Topic: How to update parameters iteratively within a Loop?
Replies: 2
Views: 206

Re: How to update parameters iteratively within a Loop?

Hi, why does your last suggestion not work? This code does what you want to accomplish: Set itera /itera1*itera5/; set l / l1*l10 /; $onempty Parameter L_avail(l,itera) / /; variable xl(l); loop(itera, if (ord(itera)>1, L_avail(l, itera) = L_avail(l, itera-1); xl.l(l) = 1$(uniform(0,1)<0.2); * Loop(...
by bussieck
4 weeks ago
Forum: Syntax
Topic: How to refresh Dynamic Set within a Loop
Replies: 2
Views: 163

Re: How to refresh Dynamic Set within a Loop

"g_ava(g)$(G_avail(g, itera)) = yes;" only assigns the values where G_avail(g, itera) is true, it does not clear/overwite the elements where G_avail(g, itera) is false. Just you it as follows: g_ava(g) = yes$G_avail(g, itera); The sparse GAMS execution will execute this as efficient as possible. -Mi...
by bussieck
1 month ago
Forum: Syntax
Topic: If Statement - Uncontrolled Set entered as a costant
Replies: 3
Views: 220

Re: If Statement - Uncontrolled Set entered as a costant

Hi, First a few ways how to improve better readability of your posts which will improve the chance that someone looks at your question: 1) I suggest that you try to boil down your issues in a small but complete example (one that one can compile and potentially execute) rather than pasting your entir...
by bussieck
1 month ago
Forum: Syntax
Topic: Exit Code -1073740791
Replies: 2
Views: 135

Re: Exit Code -1073740791

Hard to work with this little information. A negative exit code often means that the OS had issues starting the process. As far as I know gdxrrw does not actually run GAMS jobs, it just helps reading and writing GDX files. How do you start GAMS jobs and what kind of output do you get? It might help ...