Here, you can find FAQs, some (hopefully useful) hints, a bug report system etc. The website is managed with Wiki, which means that every user can edit the webpages from the regular web browser. In particular, we encourage IPOPT users to share their experiences and usage hints on the ``Success Stories'' and ``Hints and Tricks'' pages, or to list the publications discussing applications of IPOPT in the ``Papers related to Ipopt'' page6. In particular, if you have trouble getting IPOPT work well for your optimization problem, you might find some ideas here. Also, if you had some difficulties to solve a problem and found a way around it (e.g., by reformulating your problem or by using certain IPOPT options), it would be very nice if you help other users by sharing your experience at the ``Hints and Tricks'' page.
IPOPT is an open source project, and we encourage people to contribute code (such as interfaces to appropriate linear solvers, modeling environments, or even algorithmic features). If you are interested in contributing code, please have a look at the COIN-OR contributions webpage7 and contact the IPOPT project leader.
There is also a mailing list for IPOPT, available from the webpage
We try to answer questions posted to the mailing list in a reasonable manner. Please understand that we cannot answer all questions in detail, and because of time constraints, we are not able to help you model and debug your particular optimization problem.
Another way for discussion and contributing to IPOPT is via its presence on GitHub:
A short tutorial on getting started with IPOPT is also available .