Search found 5 matches

by ElChapo
6 years ago
Forum: Solvers
Topic: Change Options for IPOPT in GAMS Project
Replies: 0
Views: 2557

Change Options for IPOPT in GAMS Project

Hey guys,

is there a way to change the IPOPT options within the GAMS code?
What I want to do is to change the initial starting point and the initial dual-variables, as well as the barrier-parameter and the slack variable, in a loop within the GAMS project.
Hope someone can help.

Thanks!
by ElChapo
6 years ago
Forum: Solvers
Topic: IPOPT: cold-start and warm-start in one script
Replies: 0
Views: 2862

IPOPT: cold-start and warm-start in one script

Hey guys , Am trying to implement a distributed optimization in gams. Therefore I'm trying to perform one iteration of 3 non-linear optimization problems, in a loop. After each iterations variables are exchanged between the 3 systems. So, my problem is now: I want to perform a cold start at the firs...
by ElChapo
6 years ago
Forum: Syntax
Topic: Using Indices in Model Set
Replies: 4
Views: 4775

Re: Using Indices in Model Set

Yeah solved the Problem now. Wanted to do something like: summarize for all (l notequal i) (Line 3) And the vocabulary I was using wasnt right. But didnt find a quick solution, so I had to write all the summands explicitly. Problem solved but I#M wondering if there is a more elegant way. Do you know...
by ElChapo
6 years ago
Forum: Syntax
Topic: Using Indices in Model Set
Replies: 4
Views: 4775

Re: Using Indices in Model Set

Yeah I managed to solve it, problem was mainly the summation.

Code: Select all

Alias(i,j);
Wanted to do something like:
summmarize for all (l notequal i)
(Line 3)
But had to write all the summands on my own.
Do you know if there is a possibility to do so?
by ElChapo
6 years ago
Forum: Syntax
Topic: Using Indices in Model Set
Replies: 4
Views: 4775

Using Indices in Model Set

Can I use indices in a model definition? I'm trying to solve models with different indices, but somehow get multiple erros. 1: EQdp(i) .. dp(i) =e= x(i,'P_gen')-P_L(i)-sum(j,(x(i,'theta')-x(j,'theta'))*B(i,j)) 2: EQg(i) .. 0 =e= EQdp(i) 3: EQcost(i) .. cost(i) =e= sum(gen,co(gen,'a')+co(gen,'b')*x(g...