Search found 1042 matches

by bussieck
8 months ago
Forum: Syntax
Topic: how to use a single subscript variable
Replies: 4
Views: 5964

Re: how to use a single subscript variable

If each stock belongs exactly to one sector, you can change SC(s,i) to SC(i) because the sector is implicit for a given i. You can work with a map si(s,i) that tells GAMS about what stocks belong to what sector. In your algebra, you can use the map to access the sector (and it's data) if you iterate...
by bussieck
9 months ago
Forum: Solvers
Topic: SBB Scaling
Replies: 2
Views: 5538

Re: SBB Scaling

SBB itself dooes not do any scaling, but it runs NLP solvers to solve the relaxed model, these solvers, e.g. Conopt, will do scaling.

-Michael
by bussieck
9 months ago
Forum: Solvers
Topic: Full CPLEX license issue
Replies: 1
Views: 4890

Re: Full CPLEX license issue

I suggest you contact sales or support at gams.com. Too many things depend on you license and the forum won't be able to fix this.

-Michael
by bussieck
9 months ago
Forum: API
Topic: Java Api - change set entries in ModelInstance via Modifier or else
Replies: 2
Views: 4358

Re: Java Api - change set entries in ModelInstance via Modifier or else

No, this is not possible. GAMSModelinstance only works with a fixed model rim. Sets change the model rim. The solution to this is to initiate the GAMSModelinstance with the full set of a possible subsets and use 0 (actually EPS) in the equation aalgebra (via some modifiable parameter) when you don't...
by bussieck
9 months ago
Forum: Syntax
Topic: how to use a single subscript variable
Replies: 4
Views: 5964

Re: how to use a single subscript variable

Hi, I don't know what you mean by this But now, having to write it professionally Almost all GAMS model have multiple indexes, this is as professional as it gets. There are ways to ""flatten" the index space, but that looks very ugly, so before suggesting ways to do this, I would like...
by bussieck
9 months ago
Forum: Solvers
Topic: BARON .how to use .EquaClass option?
Replies: 1
Views: 5021

Re: BARON .how to use .EquaClass option?

Since you haven't gotten any answer, I suggest to share the model to make this reproducible. -Michael
by bussieck
9 months ago
Forum: Bugs
Topic: Studio runs when first opened but then gives an error
Replies: 2
Views: 4599

Re: Studio runs when first opened but then gives an error

Rob, Studio adds a couple of parameters to the GAMS command line. Obviously, the last one pf="." is wrong. pf points to a GAMS parameter file with more command line options. Studio recently introduced the "GAMS Parameter File" feature, see https://www.gams.com/latest/docs/T_STUDI...
by bussieck
9 months ago
Forum: Modeling
Topic: How to accelerate variable multiplication calculation.
Replies: 1
Views: 3334

Re: How to accelerate variable multiplication calculation.

The steps that takes long is the extraction of the Q matrix from the non-linear instructions. There are basically two algorithms to do this and we default to the one (ThreePass) that is is fast in most cases. You might benefit from using the other algorithm (DoubleForward). We even have a "conc...
by bussieck
9 months ago
Forum: Announcements
Topic: GAMS Distribution 44.0.0 (Beta Release)
Replies: 0
Views: 18584

GAMS Distribution 44.0.0 (Beta Release)

Hi GAMS Users, We would like to announce the availability of the GAMS Beta Release 44.0.0. Please consult the beta release notes for details about new features and updated solvers: https://www.gams.com/beta/docs/RN_44.html If you are interested in experimenting with this beta release, please downloa...
by bussieck
9 months ago
Forum: Syntax
Topic: Table Error 225
Replies: 1
Views: 4837

Re: Table Error 225

I guess some mix with TAB and spaces to get the table aligned. I would remove TABs whereever possible and go with spaces only. If that's not the case you should upload (not copy paste because too much can change) the model file so one can reproduce.

-Michael