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Our data sets of established and new test models are in the form of GAMS data exchange (.GDX) files. Running GAMS LINLib models using .GDX files is exactly the same as running regular GAMS models.


Running GAMS LP and MIP models using .GDX files

The general command for LP is: 
     >> gams (modelname) lp=(solvername)
The model is determined by the data that is inputted through the use of .GDX files. The user need not worry about including this - it is done automatically by the particular GAMS model. A sample LINLib LP model is blend.gms.

Now as a specific example, suppose we want to run the model blend, which makes use of the data file blend.gdx. From the command line the syntax for running the model blend.gms using, for example the solver XA is: 
     >> gams blend lp=XA
The command for running MIP models is similar as for LPs: 
     >> gams (modelname) mip=(solvername)
Again, the user specifies the solver using the GAMS option mip=(solvername). A sample LINLib MIP model is 10teams.gms.


Running LINLib models from the GAMS IDE

If we were to run LINLib models from the GAMS IDE, we would specify 
     --gdxfile=(modelname) lp/mip=(solvername)
in the GAMS parameter list box.


Structure of LINLib models

Each GAMS LP model using .GDX data files in the Performance Library is a generic LP model, containing all possible equation and variable types that may exist in an LP. The model is determined by the data that is inputted through the use of .GDX files. The user need not worry about including this explicitly - it is done automatically by the particular GAMS model. Similarly, each MIP model in LINLib is a generic MIP model containing all possible variabel and equations types.