GAMS World Forum

What does the error message say?

I am using SCIP to solve an MINLP. Since I do not have a full licence for SCIP with GAMS, I am exporting the model in OSIL format and input it in the SCIP system provided by Zuse. My model contains constraints smax(x1,x2,x3,...) => a When solving a small instance using the demo GAMS/SCIP I don't enc...

Hello Michael Thank you very much for your help. Perhaps it is better to show what I intend to do. I would like to implmenet the following constraints. Constr(j,t).. sum(i,sum(m$((ord(m) ge ord(t)) and (ord(m) le (ord(t) + d(i,j) - 1))), W(i,m,j))) =L= C(j) Set j /U1, U2/ ; Set i /T1, T2/ ; Set t /1...

I cannot figure out how to correctly define the following SOS1 variable. SOS1 Variable W(j,m,i) ; where Set j /U1,U2/ ; Set i /T1,T2/ ; Set t /1*10/ ; Set m /t * t+p(i,j)-1/ ; SOS1 Variable W(i,m,j) ; For example, If p(i,U1) = 2 and t = 1 the SOS1 set should comprise the variables W(T1,1,U1), W(T1,2...

Thank you very much for your reply. My question is somehow more complex. I am generating equations eq(i,j,s), where i,j,s are sets. It happens that equations eq(i,j,"s1") and eq(i,j,"s2") are identical. This is because the values of s are not included in the output of the gams eq...

Hello I would like to conditionally write constraints. In order to explain what I mean, consider the following example Let i, s be sets. s = {a,b} i = {1,2} The statement eq(i,s).. generates the equations eq(1,a), eq(1,b), eq(2,a), eq(2,b) I would like to tell GAMS to only generate equations by only...

This is exactly what I needed.

Thank you very much!

I would like to express the following in GAMS using its MAX(x1,x2,...,xn) function. max {B(i,j)¦i in Ij} for all valid combinations of (i,j) where i={i1,i2,...,in}, j={j1,j2,...,jk). So, the GAMS-determined result could be something like this MAX(B(i1,j1), B(i2,j1), B(i5,j1)) =l= ... MAX(B(i1,j2), B...

Thank you very much!

I suppose you mean that

B(i1,j,t) * B(i2,j,t) * B(i3,j,t) =e= 0

implies that at least one of the Bs has to be zero while SOS1 means that at most one of the Bs is nonzero.
This is ok for my model.

I would like to model the following in GAMS B(i1,j,t) + B(i2,j,t) + B(i3,j,t) =l= V , B(.,.,.) nonnegative variables and V a constant. B(i1,j,t) * B(i2,j,t) * B(i3,j,t) =e= 0 I would like to solve the problem using SOS1 sets. The triplet B(i1,j,t), B(i2,j,t), B(i3,j,t) forms a SOS1. How can I transl...