[Ipopt] Negative Lagrange multipliers?

[Ipopt User]

IPOPT treats all constraints as equalities with slacks, see (2b) in
http://www.optimization-online.org/DB_FILE/2004/03/836.pdf

On Tue, Sep 6, 2016 at 8:21 PM, Chunhua Men <chhmen at gmail.com> wrote:

> Hi, I used IPOPT 3.12.4 to solve a constrained model, and chose
> "limited-memory" as the Hessian approximation. My coding environment is
> visual studio C++.  IPOPT converged to optimal solution.  I wanted to know
> the Lagrange multiplier for each constraint, so I printed out "lambda" in
> "finalize_solution". However, many of them were negative. Did I miss
> anything?
>
> Thanks, Chunhua
>
>
>
> _______________________________________________
> Ipopt mailing list
> Ipopt at list.coin-or.org
> https://urldefense.proofpoint.com/v2/url?u=http-3A__list.
> coin-2Dor.org_mailman_listinfo_ipopt&d=CwICAg&c=Ngd-
> ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=Krbuvr0BfvPSQKvQuiGrWIUfVTj8ke
> dnZerudAN3FWE&m=a_2DH1-JLrp3dNBIbx05pyyLwb4LVhtnTgXAs
> 8ZvlR0&s=Pl6RJRxVCqHGy-wEIKdnxo1N2UcAlQGXpBY_LA2CTHY&e=
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/ipopt/attachments/20160907/6a5a76a6/attachment.html>