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For a model in LINLib we have collected points which represent some solution to a problem. The points are part of the library and are in GAMS data exchange (GDX) format. They are identified by the model name plus the extension _p1.gdx, _p2.gdx, etc. For example, the model 10teams has a solution point 10teams_p1.gdx.

The header of the point file contains details of the point, for example objective function value at that point and solver used to obtain the solution. The file page also contains model statistics such as number of variables, discrete variables, constraints, etc. For details the user is referred to a point page such as 10teams_p1.



Running MIP models from specific points

In order to start a MIP model from a certain point users can run GAMS in the following way:
     >> gams (modelname) --point=(point number) optfile=1
where
        --point=p1 (p2, p3, etc.)
The option --point=(point number) tells GAMS to use a feasible point, where the --point value is the point number (p1, p2, p3, etc.).

For MIP models, users will also have to create an option file for the specific solver used in order to tell it to use the restart point. For example, for CPLEX one would create an option file cplex.opt with the entry
mipstart 1
Furthermore, users need to include the optfile=1 option to specify that a solver option file is used.



Running LP models from specific points

If users with to make use of a starting point for LPs, the syntax is similar as for MIP models.
     >> gams (modelname) --point=(point number)
No solver option file is necessary to tell GAMS to use the point.