Hello Ray,
thanks a lot for the reply. So, if I get it right the suc=1 does not mean 
necessarily at all that everything went right. From what I understood, whenever 
there is a constrained violated there are outputs that tell you which got 
violated (extra prints for gen and branch constraints). So in order to make my 
code more eefficient and avoid all these checks is there a way to get to know 
if at least one constraint got violated, for example somehow accessing these 
extra prints?
Thanks once more,
Vagelis 

From: [email protected]
Subject: Re: OPF questions
Date: Mon, 1 Oct 2012 10:20:50 -0400
To: [email protected]

On Sep 30, 2012, at 3:06 PM, Evangelos Galinas <[email protected]> 
wrote:1st: Is there a way to tell to the opf function to disregard the power 
limits of Generators (min/max) or the branch flow limits? Or I have to change 
the limits myself accrdingly in the system struct before I run a new OPF?
You have to change the limits in the case data before running. Btw, setting 
RATE_A for a line to zero removes the branch flow limit.
2nd: I realised that the suc value get zero only if the algortihm does not 
converge. What I need to know for my implementation though, is at any point to 
know if even one contraint (generator or branch) was violated. Is there a way 
to quickly access a flag or something for that, or I'll have to do checks 
myself between the 2 colums (e.g. Pg and Pmax) after every run? Alternatively, 
maybe you have a more efficient way to do that?
If the OPF converges successfully all constraints will be satisfied. If it does 
not converge successfully, the values returned are not necessarily meaningful 
at all. Specifically, I don't know of any of the solvers that will return a 
solution with all constraints satisfied except a few that are conflicting.
In general, determining the minimal number of changes required to make an 
infeasible problem become feasible is a difficult problem.

-- Ray ZimmermanSenior Research Associate419A Warren Hall, Cornell University, 
Ithaca, NY 14853phone: (607) 255-9645
                                          

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