[Ipopt] Slack variables too small

Fabio Ronchini fabio.ronchini at studenti.unipr.it
Tue Mar 13 18:04:42 EDT 2018

Hello everyone,

I am having a hard time with Ipopt to minimize the curve length of a curve
family. In the optimization problem I have no constraints, and all six
variables are chosen in a compact interval.

During the optimization process, Ipopt prints "6 slacks too small,
adjusting variable bounds", then performs a new iteration. It all repeats
for the last four iterations and then exits with "EXIT: Optimal solution
found", giving me a solution which is clearly NOT the shortest curve. Also
the gradient vector shows clearly that this is not a local minimum.

I fear this variable bounds adjustments may interfere with the optimization
process, but I have found nothing in the documentation about what this is
or how can one control it. Can someone help, please?


Fabio Ronchini

priva di virus. www.avg.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/ipopt/attachments/20180313/85439a61/attachment.html>

More information about the Ipopt mailing list