NEOS Server Home

NEOS Interfaces to MINOS

WWW Form & Sample Submissions


The NEOS Server offers MINOS for the solution of nonlinearly constrained optimization problems in AMPL format. MINOS is suitable for large constrained problems with a linear or nonlinear objective function and a mixture of linear and nonlinear constraints. It is most efficient if the constraints are linear and there are not too many degrees of freedom.

For linear programs, MINOS uses a stable implementation of the primal simplex method. For linearly constrained problems, a reduced-gradient method is employed with quasi-Newton approximations to the reduced Hessian. For nonlinear constraints, MINOS implements a sequential linearly constrained algorithm derived from Robinson's method. Step length control is heuristic, but superlinear convergence is often achieved. Additional information on MINOS can be found in the Using AMPL/MINOS Guide.

MINOS was developed by Bruce A. Murtagh and Michael Saunders.

Using the NEOS Server with MINOS

The user must submit a model in AMPL format to solve a nonlinear programming problem. Examples of models in AMPL format can be found in the netlib collection.

The nonlinear program is specified by a model file with the options of a data file and a commands file. If the commands file is specified, it must contain the AMPL solve command. The commands file must not contain the model or data commands. The model and data files are renamed internally by NEOS.

The commands file may include AMPL commands or set solver options for MINOS. To specify solver options, add

option minos_options "OPTIONS";
where OPTIONS is a list of one or more of the MINOS options, which are listed in the Using AMPL/MINOS Guide.

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
Dry run: generate job XML instead of submitting it to NEOS
Short Priority: submit to higher priority queue with maximum CPU time of 5 minutes
E-Mail address:
Please do not click the 'Submit to NEOS' button more than once.