
gams mymodel dumpopt=11This will create a file mymodel.dmp which represents a self contained version of the original model.
CONVERT has options that impact the translation. For example, for a cone model the option CONEREFORM creates an NLP rather than a scalar cone problem. Please refer to the CONVERT manual on the GAMS web page for all options.
In the GAMS model that you are going to submit, you can add options to the CONVERT option file in the following way:
... $ontext >> convert.opt conereform 1 objvar myobjvar $offtext solve mymodel min obj using lp;Important: You need to append to ">>" rather than create ">" the CONVERT option file. Otherwise, gms2xx will not work properly.
The GMS2XX translator is transforming GAMS models into a very simple internal scalar format. A model that is passed on to a solver can be seen as a linear list of variables, X1 to Xn, a linear list of equations or constraints, E1 to Em, plus the relationship between these variables and equations represented in some form. This internal format of a single model can then be written out in many different formats. With GAMS as output format, the scalar model consists of
All operations involving sets are unrolled, and all expressions involving parameters are evaluated and replaced by their numerical values. Since there are no sets or indexed parameters in the scalar models, most of the differences between modeling systems have disappeared. The GAMS format is therefore very easy to transform into the format of another language.
The proprietary parts of an industrial model are usually hidden in the names of sets, parameters, variables, and equations; the names of set elements, the numerical values of parameters, the structure of the symbolic equations, and the relationships between these items. During the translation of a userwritten GAMS model into scalar format, most of this information is lost. All that is left is the size of the model, the structure of the Jacobian, and some linear and nonlinear relationships with numerical coefficients. The developer of a model will often not even be able to recognize his own model. Industrial users with an interest in improving the solvers they use themselves can therefore in many cases release the scalar version of their model to a model library like MINLPLib.
alpha.ecp  The model in AlphaECP scalar format 
ampl.mod  The model in AMPL scalar format 
amplnlc.c  The model in C code 
coinfml.xml  The model in CoinFML XML format 
convert.opt  The option file used to translate the model to the requested format 
cplex.lp  The model in CPLEX LP format 
cplex.mps  The model in CPLEX MPS format 
dict.txt  The dictionary of the model 
fixed.mps  The model in FIXED MPS format 
gams.bar  The model in BARON scalar format 
gams.gms  The model in GAMS scalar format 
gamsmcp.gms  The model in GAMS MCP format with added KKT conditions 
jacobian.gdx  A GDX file containing the basic model data 
lago.gms  The model in LaGO GAMS scalar format 
lgomain.for  The model as a Fortran subroutine (used by LGO) 
lindo.mpi  The model in LINDO MPI format 
lingo.lng  The model in LINGO scalar format 
minopt.dat  The model in MINOPT scalar format 
vienna.dag  The model in VIENNA DAG scalar format 
For questions or comments please contact the Performance World managing editor.