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Supported Sub Solvers

In order to use GAMS/BARON, users will need to have a GAMS/BARON license as well as a licensed GAMS linear programming (LP) solver. A licensed GAMS nonlinear programming (NLP) solver is optional and usually expedites convergence. By default, GAMS/BARON will attempt to use CPLEX as the LP solver and MINOS as the NLP solver. If the user does not have licenses for these solvers, then the user must use the options LPSol and NLPSol to specify another LP or NLP solver.

  • Currently the valid LP solvers are CPLEX, MINOS, SNOPT, and XPRESS.
  • Purchasing a high-performance LP solver like CPLEX, or XPRESS is highly recommended since the LPs that GAMS/BARON solves can become quite large and difficult.
  • As NLP solvers all GAMS NLP solvers can be used. While MINOS and SNOPT can be chosen using the option nlpsol = 2 and nlpsol = 4, respectively, all other solvers can be chosen via nlpsol = 6 and the addition option ExtNLPSolver. E.g ExtNLPSolver = conopt.1 will instruct Baron to use Conopt with an option file conopt.opt.
  • GAMS/BARON will not work if CONOPT is the only available solver. While CONOPT can solve LP problems independent of GAMS/BARON, it is not available as an LP solver within GAMS/BARON.
  • GAMS/BARON can be used without an NLP solver by setting DoLocal = 0 and NumLoc = 0 in a GAMS/BARON option file. Please consult §4 of the GAMS/BARON manual for further information.

A minimal GAMS/BARON system requires any one of the CPLEX, MINOS, SNOPT, or XPRESS solvers together with the appropriate options. For example, if only XPRESS is available the following options need to be set:

lpsol   7 # select XPRESS as the LP solver
dolocal 0 # turn off local search with an NLP solver
numloc  0 # see dolocal

If only SNOPT is available, we can use SNOPT for solving the LP and NLP problems. Hence the appropriate option file would look like

lpsol   4 # select SNOPT as the LP solver
nlpsol  4 # select SNOPT as the NLP solver
IMPRESSUM / LEGAL NOTICEPRIVACY POLICY solver/supported_sub_solvers.1317903582.txt.gz · Last modified: 2011/10/06 14:19 by support