The NEOS Server offers Couenne for the solution of mixed-integer
nonlinearly-constrained (MINLP) and global optimization problems.
Problems can be submitted to Couenne on the NEOS server in AMPL or GAMS
Couenne (Convex Over and Under ENvelopes for
Nonlinear Estimation) is a branch-and-bound algorithm to solve
mixed integer nonlinear programs (MINLPs) and global optimization problems.
Couenne aims to find global optima of nonconvex MINLPs. It implements
linearization, bound reduction, and branching methods within a
branch-and-bound framework. Its main components are:
Couenne was developed and is currently maintained by Pietro Belotti and
others. More details on the solver are available on the
Couenne page at COIN-OR.
The user must submit a model in GAMS
format to solve an optimization problem. For security purposes, the model
submitted must adhere to the following conventions:
If you are unfamiliar with GAMS, the
GAMS Documentation includes a
GAMS Tutorial and
Examples of models in GAMS format can be found in the
GAMS model library.
By default, the NEOS Server limits the amount of output generated in the listing
file by turning off the symbol and unique element list, symbol cross references,
and restricting the rows and columns listed to zero. This behavior can be changed
by specifying the appropriate options in the model file. See the
documentation on GAMS output
for further information.
You may optionally submit an options file if you wish to override the default parameter settings for the solver.
Currently, the NEOS Server can only use optfile=1 with GAMS input. Therefore, any model that specifies a different options file will not work as intended.
<modelname>.optfile = 1 ;
optfile = 1