Search found 372 matches
- 3 years ago
- Forum: Modeling
- Topic: Variable Start-up cost in the Unit Commitment Problem
- Replies: 4
- Views: 3400
Re: Variable Start-up cost in the Unit Commitment Problem
When you run set i / -2, -1, 0, 1, 2 /; you should get the following error which is very explicit about UNQUOTED elements having to start with a letter or digit. 1 set i / -2, -1, 0, 1, 2 /; **** $338$338 $172$172 **** 172 Element is redefined **** 338 Unique element expected - symbol was not an ele...
- 3 years ago
- Forum: Archive Google Group
- Topic: GAMS Studio dark mode
- Replies: 2
- Views: 12156
Re: GAMS Studio dark mode
Yes, see https://www.gams.com/latest/docs/T_STUD ... O_SETTINGS
For Windows the dark theme was introduced in Studio version 0.14.6.
If you download the latest GAMS from https://www.gams.com/download/ you get Studio version 1.1.0 and should be good.
I hope this helps!
Fred
For Windows the dark theme was introduced in Studio version 0.14.6.
If you download the latest GAMS from https://www.gams.com/download/ you get Studio version 1.1.0 and should be good.
I hope this helps!
Fred
- 3 years ago
- Forum: Tools
- Topic: International characters
- Replies: 1
- Views: 2704
Re: International characters
Hi, I guess that you are executing GAMS in a directory with non-ASCII characters. GAMS has trouble with this. Please run GAMS in a directory that does only contain [a-zA-Z] characters. If this is not possible (because your home directory already has non-ASCII characters in it) choose a solveLink opt...
- 3 years ago
- Forum: Modeling
- Topic: Warehouse Problem with minimizing the net present value of the cost
- Replies: 2
- Views: 7855
Re: Warehouse Problem with minimizing the net present value of the cost
Hi, Problem is how you use set t at the end of equation cost.. TC =e= sum[t, [{SP(t)*(buy(t)-sell(t))+SC*stock(t)}/((1+i)**t)]]; While you use set elements 1,2,3,4, set elements can in general be strings (e.g. apple, orange, cherry, ...) which is why you cannot make calculations with set elements li...
- 4 years ago
- Forum: Syntax
- Topic: Run a program
- Replies: 4
- Views: 3232
Re: Run a program
What I suggested was a way to get your own license, free of charge, that allows you to solve the model yourself. The license type is called a community license (https://www.gams.com/latest/docs/UG_License.html#GAMS_Community_Licenses). I thought that you would probably prefer being able to solve you...
- 4 years ago
- Forum: Syntax
- Topic: Run a program
- Replies: 4
- Views: 3232
Re: Run a program
Your model fits in the community license limits (https://www.gams.com/latest/docs/UG_Lic ... y_Licenses)
You can contact sales@gams.com to request such a license.
I hope this helps!
Fred
You can contact sales@gams.com to request such a license.
I hope this helps!
Fred
- 4 years ago
- Forum: Modeling
- Topic: Questions about the Results
- Replies: 4
- Views: 2739
Re: Questions about the Results
Actually, the output was right. Your idea of what the output should be like was wrong. Hard to have this fixed by a debugging tool ;-) When facing a problem as the one described in your initial post, it is often a good idea to have a look at the equation listing and column listing to check whether t...
- 4 years ago
- Forum: Modeling
- Topic: Cplex generates optimal solution but then declares it to infeasible
- Replies: 3
- Views: 2474
Re: Cplex generates optimal solution but then declares it to infeasible
Hi Nikou,
Can you share an example, so other forum users can reproduce the observed behavior.
Would also be interesting to know which version you are using.
Best,
Fred
Can you share an example, so other forum users can reproduce the observed behavior.
Would also be interesting to know which version you are using.
Best,
Fred
- 4 years ago
- Forum: Syntax
- Topic: Infeasibilities in loop solve using CPLEX
- Replies: 3
- Views: 8140
Re: Infeasibilities in loop solve using CPLEX
Hi Petros, Happy to read that you solved your problem. However, to avoid confusion, I would like to mention that that the mipstart option has little to do with your initial problem. You wrote that Cplex returns infeasible for your model. Instructing Cplex to use a starting point (which is what you d...
- 4 years ago
- Forum: Syntax
- Topic: BCH | Cplex | Branch and Cut
- Replies: 6
- Views: 4407
Re: BCH | Cplex | Branch and Cut
Hi Jonathan, To avoid confusion, let's call your first approach "BCH approach" and the second approach "loop approach". I get your idea but there is no such syntax that allows you to do something like =*sense_c(allcuts)*= with the loop approach. The sense_c and rhs_c stuff is des...