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NEOS Interfaces to LANCELOT

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The NEOS Server offers LANCELOT for the solution of nonlinearly constrained optimization problems in AMPL format. LANCELOT is suitable for large nonlinearly constrained problems.

LANCELOT implements an augmented Lagrangian algorithm. Additional information on LANCELOT can be found in the User's Guide for LANCELOT .

LANCELOT was developed by Andy Conn, Nick Gould , and Philippe Toint.

Using the NEOS Server for LANCELOT

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

The model is specified by a model file, and optionally, a data file and a commands file. If the command file is specified it must contain the AMPL solve command.

The commands file can contain any AMPL command or set options for LANCELOT with, for example,
option lancelot_options "ctol=10e-03 maxit=50";
Printing directed to standard out is returned to the user with the output.

This NEOS solver executes on a Sun workstation. Sun, Sun Microsystems, the Sun Logo and the Powered by Sun Logo are trademarks or registered trademarks of Sun Microsystems, Inc. in the U.S. and other countries.
Enter the location of the ampl model (local file)
Model File:

Enter the location of the ampl data file (local file)
Data File:

Enter the location of the ampl commands file (local file)
Commands File:


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:

By submitting a job, you have accepted the Terms of Use
Please do not click the 'Submit to NEOS' button more than once.

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