Search found 163 matches

by Fred
1 month ago
Forum: Modeling
Topic: Problem with creating a constraint for a minimum amount of consecutive days
Replies: 1
Views: 119

Re: Problem with creating a constraint for a minimum amount of consecutive days

Hi, I think the following example should do the trick. binary variable y(i,l) 'worker i works on day l'; variable start(i,l) 'value of 1 indicates that worker i starts to work on day l'; equation defStart(i,l) minconsec(i,l); defStart(i,l).. start(i,l) =e= y(i,l) - y(i,l-1); minconsec(i,l)$(ord(l)>1...
by Fred
1 month ago
Forum: Syntax
Topic: Error 66 even when all symbols are defined and assigned... help!
Replies: 2
Views: 157

Re: Error 66 even when all symbols are defined and assigned... help!

Hi, If you look into the listing file, the first error you get is **** $66,256,299 UNEXPECTED END OF FILE (1) **** 3 ERROR(S) 0 WARNING(S) After adding a semicolon after the solve statement yo get 79414 solve MEPI using mip minimizing of; **** $66,256 **** LINE 251 INPUT C:\Users\user\Documents\supp...
by Fred
2 months ago
Forum: Modeling
Topic: cplex error 1217 :no solution exists.
Replies: 1
Views: 130

Re: cplex error 1217 :no solution exists.

Hi, Your model is (integer) infeasible. So there is no feasible point to all the constraints and integrality requirements you have specified. You either made a mistake implementing some constraint, or the combination of model and data really allows for no feasible solution. This state of the optimiz...
by Fred
2 months ago
Forum: Modeling
Topic: Connecting GAMS 28.1.0 to neos server
Replies: 3
Views: 224

Re: Connecting GAMS 28.1.0 to neos server

Hi,

To help you it would be good to know how exactly your code fails (share log, lst and files to reproduce). If I adopt your code snippet to model from the model library, everything works as expected.

Best,
Fred
by Fred
2 months ago
Forum: Solvers
Topic: Solver stop conditions
Replies: 1
Views: 388

Re: Solver stop conditions

Hi,

The Baron options DeltaTerm, DeltaT, DeltaR, DeltaA seem to be what you are looking for: https://www.gams.com/latest/docs/S_BARO ... ermination

I hope this helps!

Fred
by Fred
2 months ago
Forum: Solvers
Topic: chance constraint
Replies: 1
Views: 117

Re: chance constraint

Hi, You might want to have a look at the stochastic Programming features of the EMP framework that allow users to model various stochastic problems as deterministic models, while information about the stochastic structure of the problem is specified in annotations. https://www.gams.com/latest/docs/U...
by Fred
2 months ago
Forum: Syntax
Topic: Error: overflow in + operation (addop)
Replies: 3
Views: 199

Re: Error: overflow in + operation (addop)

I replied to your question directly in the archive.

Fred
by Fred
2 months ago
Forum: Archive Google Group
Topic: Large Numbers
Replies: 5
Views: 785

Re: Large Numbers

Hi, it seems that the result of the assignment statement is > 1E300 which causes an overflow. Are you sure that you need such large numbers. And are you sure that you found the right line in your code? With include files this can be tricky, so I suggest to check the line number in the echo print of ...
by Fred
2 months ago
Forum: Modeling
Topic: Error 56
Replies: 1
Views: 174

Re: Error 56

Hi, If PA and W are binary variables, you are basically looking for a way to model the "product of binary variables". If you google for that, you should get lots of helpful results like e.g. http://yetanothermathprogrammingconsultant.blogspot.com/2008/05/multiplication-of-binary-variables.html I hop...
by Fred
3 months ago
Forum: Syntax
Topic: CEG Model
Replies: 7
Views: 399

Re: CEG Model

Hi, I suggest to run with command line parameter errmsg=1 (https://www.gams.com/latest/docs/UG_GamsCall.html#GAMSAOerrmsg) to reposition compilation error messages in the lst file and then go through you errors step by step by searching for four asterisks (****) in the lst file (they mark an error)....