Search found 215 matches
- 3 weeks ago
- Forum: API
- Topic: Python API picking up wrong GAMS version
- Replies: 3
- Views: 3176
Re: Python API picking up wrong GAMS version
Hello, It sounds to me like the GAMS 38 in the sitecustomize.py file is confusing your fresh conda install. Many years ago I used the Python site package, but once I started to use miniconda I dropped it completely. I found that the two don't work well together. And at some level they are fundamenta...
- 7 months ago
- Forum: Solvers
- Topic: Duality Gap
- Replies: 2
- Views: 7129
Re: Duality Gap
Hello,
I believe that the helpful users in this forum will be more inclined to offer help and better able to offer help if you follow the forum rules:
app.php/rules
BTW, the rules don't mention sending a log file, but in this case it seems like a good idea.
-Steve
I believe that the helpful users in this forum will be more inclined to offer help and better able to offer help if you follow the forum rules:
app.php/rules
BTW, the rules don't mention sending a log file, but in this case it seems like a good idea.
-Steve
- 7 months ago
- Forum: Syntax
- Topic: problem in using ord
- Replies: 1
- Views: 7249
Re: problem in using ord
Sajjad, In the example below are a couple ways to do what you ask. set i / 1*3 /; singleton set s(i); scalar counter / 1 / a / NA / b / NA / ; parameter dinf(i); dinf(i) = ord(i); a = sum{i$[ord(i) = counter], dinf(i)}; * singleton sets can have at most one member, so * we can do things with them we...
- 7 months ago
- Forum: Syntax
- Topic: How to terminate mpec sooner
- Replies: 1
- Views: 9825
Re: How to terminate mpec sooner
T_k, If you are solving your MPEC model with the NLPEC solver, than you are ultimately running a DNLP solver on a reformulated version of the problem. So the answer depends entirely on what DNLP solver you are using. Please specify. Many DNLP solvers are local solvers, i.e. they are looking for a po...
- 8 months ago
- Forum: Bugs
- Topic: Out of memory problem
- Replies: 5
- Views: 5855
Re: Out of memory problem
Wenkey, I think you have misunderstood the workfactor option: https://www.gams.com/44/docs/UG_GamsCall.html#GAMSAOworkfactor The value of 1 is the default. Anything larger than one grows the workspace used by CONOPT. 2 is a reasonable value to try. 10 is fairly aggressive. 1e299 is not reasonable. H...
- 8 months ago
- Forum: Syntax
- Topic: Changing location for lst files
- Replies: 3
- Views: 10728
Re: Changing location for lst files
Hello,
Perhaps you want to also try the workdir parameter: it might be helpful if you want to redirect many things at once.
https://www.gams.com/44/docs/UG_GamsCal ... SAOworkdir
For example do:
mkdir foo
( cd foo ; gamslib trnsport )
gams trnsport workdir=foo lo=4
ls foo
HTH,
-Steve
Perhaps you want to also try the workdir parameter: it might be helpful if you want to redirect many things at once.
https://www.gams.com/44/docs/UG_GamsCal ... SAOworkdir
For example do:
mkdir foo
( cd foo ; gamslib trnsport )
gams trnsport workdir=foo lo=4
ls foo
HTH,
-Steve
- 9 months ago
- Forum: Modeling
- Topic: arrangement of LHS and RHS in equality equations (MCP)
- Replies: 2
- Views: 5563
Re: arrangement of LHS and RHS in equality equations (MCP)
Tatjana, You are asking some good questions here, questions that get to the foundations of what an MCP model really is. Fundamentally, MCP is not about equations and inequalities. It is about function-variable pairs, and the relationships dictated by those pairs. I could say a lot here, but it would...
- 9 months ago
- Forum: Modeling
- Topic: use of subset
- Replies: 4
- Views: 4771
Re: use of subset
Zorro, I encourage you to look at the GAMS model library: anywhere is probably useful, but start with the trnsport and dice models if you don't have other ideas. You will observe that using multiply-indexed variables is the normal practice. There is nothing unprofessional about this. It is very much...
- 10 months ago
- Forum: Syntax
- Topic: JAMS Pre processing failed
- Replies: 5
- Views: 10679
Re: JAMS Pre processing failed
Omar,
This seems like a trick question. The solve statement does not include any equations. For example:
contains no equations and only one variable.
-Steve
This seems like a trick question. The solve statement does not include any equations. For example:
Code: Select all
solve myMod using emp min z;
-Steve
- 10 months ago
- Forum: Syntax
- Topic: JAMS Pre processing failed
- Replies: 5
- Views: 10679
Re: JAMS Pre processing failed
Hello, You are getting closer. Have a look at the transbp model in EMPLIB: it demonstrates the use of indexed equation and variable symbols in the EMP info file. The EMP info file in that example looks like this: bilevel min z x cost supply demand vi extdem g with no index sets with the equation and...