NEOS Interfaces to Ipopt

Sample Submissions


The NEOS Server offers IPOPT for the solution of nonlinear programs. Problems can be submitted to IPOPT on the NEOS server in AMPL or GAMS format.

IPOPT is an open-source software package for large-scale nonlinear optimization. It implements a primal-dual interior point algorithm, which uses a filter line-search method to ensure global convergence.

The main authors of IPOPT are Andreas Wächter and Carl Laird, with additional development by Lorenz T. Biegler, Arvind Raghunathan, and Yi-Dong Lang. For more information, see the IPOPT home page. A list of papers and publications describing the algorithm is available here.

Using the NEOS Server for Ipopt/AMPL

The user must submit a model in AMPL format. Examples are provided in the examples section of the AMPL website.

The problem must be specified in a model file. A data file and commands files may also be provided. If the commands file is specified, it must contain the AMPL solve command; however, it must not contain the model or data commands. The model and data files are renamed internally by NEOS.

The commands file may include option settings for the solver. To specify solver options, add

  option ipopt_options 'OPTIONS';
where OPTIONS is a list of one or more of the available solver options for AMPL.

Web Submission Form
Model File
Enter the location of the AMPL model (local file)
Data File
Enter the location of the AMPL data file (local file)
Commands File
Enter the location of the AMPL commands file (local file)
Additional Settings

E-Mail address:
Please do not click the 'Submit to NEOS' button more than once.