NEOS Server Home

NEOS Interfaces to icos

WWW Form & Sample Submissions


The NEOS Server offers ICOS for the solution of continuous, numerical constraint satisfaction problems and global optimization problems formulated in scalar AMPL format.

ICOS uses linear relaxations, filtering methods, and interval arithmetic to determine the solutions of the given problem. Default options are used. For some background see the papers by the author Yahia Lebbah. For the optimization version, see here.

This solver was implemented by Hans Mittelmann and executes at

Using the NEOS Server for ICOS

The user must submit a problem in AMPL format. Examples of models in AMPL format can be found in the ICOS distribution. The numbers of variables and constraints should be moderate.

Different from full AMPL, the submitted file should contain a self-contained model in scalar format, no data file or other commands. See here and the sample submission problems.

Web Submission Form
AMPL model for satisfiability problem (scalar format, no comands)
AMPL model for global optimization problem (scalar format, no comands)
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.