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
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
For more information, see the IPOPT home page. A list of
papers and publications describing the algorithm is available here.
The user must submit a model in AMPL
format. Examples are provided in
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';