Search found 108 matches
- 6 years ago
- Forum: Syntax
- Topic: remove element from a set
- Replies: 2
- Views: 4860
Re: remove element from a set
Hi, in main file: *You just comment or uncomment according to your needs *$include SetDefWithA.gms $include SetDefWithoutA.gms *$include SomeOtherSetDef.gms And you can have: SetDefWithA.gms Set G /'A','B','C'/ G1(G) /'A','B'/ G2(G) /'A','C'/; SetDefWithoutA.gms Set G /'B','C'/ G1(G) /'B'/ G2(G) /'C...
- 6 years ago
- Forum: Syntax
- Topic: Especify a variable value
- Replies: 1
- Views: 2595
Re: Especify a variable value
Hi, perhaps this correct example will help you: set t /t0*t100/; set w /w1*w4/; set j /j1*j10/; set o /o1*o10/; variables x,y,z; equations r3,r4,r5,r6; equation fobj; fobj.. z=e=x('j1','t2'); R3(t,w)$(ord(t) gt 0 and ord(t) lt 33 and ord(w) eq 1).. sum(j,x(j,t)) =L= sum(o,(y(o,w))); R4(t,w)$(ord(t) ...
- 6 years ago
- Forum: Syntax
- Topic: remove element from a set
- Replies: 2
- Views: 4860
Re: remove element from a set
Hi, I don't know if it fits your workflow, but, using $include of different set definitions in different files is a possibility that comes to mind. Then you just comment/uncomment the ones you are currently using. This has the advantage that you can make this kind of edits easily with your text edit...
- 6 years ago
- Forum: Solvers
- Topic: Dual infeasible due to empty column
- Replies: 1
- Views: 5725
Re: Dual infeasible due to empty column
Hi, you have a real problem, not just an artifact generated by presolve. You can see that the primal problem is unbounded. This means the objective function can get "as low as possible" if minimizing or the opposite if maximizing.
- 6 years ago
- Forum: Tools
- Topic: Is there any information stored between runs from the IDE ?
- Replies: 0
- Views: 3449
Is there any information stored between runs from the IDE ?
So far our understanding has been that no information is stored between two runs fired up from the GAMS IDE. If this is true, every symbol should be initialized in the same way, when comparing two runs. But, we have been able to reproduce a weird behaviour that challenges this understanding: Run 1: ...
- 6 years ago
- Forum: Tools
- Topic: Command línea use of gams
- Replies: 1
- Views: 3471
- 6 years ago
- Forum: Modeling
- Topic: how to model two positive variables without being positive at the same time
- Replies: 1
- Views: 3172
Re: how to model two positive variables without being positive at the same time
A quick search turns up this reference, for some cases. https://minds.wisconsin.edu/handle/1793/57916 .
My gut tells me it will be very hard to stay in LP but I haven't really made a deep search.
Good luck !
My gut tells me it will be very hard to stay in LP but I haven't really made a deep search.
Good luck !
- 6 years ago
- Forum: Tools
- Topic: 2 scrpits in one window
- Replies: 2
- Views: 6294
Re: 2 scrpits in one window
Not that I know of, for such tasks I use an external text editor. If you are willing to go that route but want extra support perhaps this is useful https://github.com/lolow/sublime-gams . I haven't tested it yet.
- 6 years ago
- Forum: API
- Topic: Installing Python API
- Replies: 7
- Views: 13142
Re: Installing Python API
Seems to be working perfectly. Thank you Clemens!
- 6 years ago
- Forum: Modeling
- Topic: Complex expression as intermediate vairable
- Replies: 1
- Views: 4546
Re: Complex expression as intermediate vairable
Not that I know of. But,
a- CONOPT in fact encourages this https://gams.com/latest/docs/solvers/co ... XPRESSIONS
b- You should experiment if it really affects model solving performance. My guess is it shouldn't in most cases.
a- CONOPT in fact encourages this https://gams.com/latest/docs/solvers/co ... XPRESSIONS
b- You should experiment if it really affects model solving performance. My guess is it shouldn't in most cases.