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The models

The original algebraic models have been translated into a scalar format in
which documentation and comments have been removed, sets and set operators
have been unrolled, and the original data and structure of the model have
disappeared. This kind of model represenation has the advantage of an easy
translation into different languages and also hides propriotary
information. The latter is neccessary because the library contains
confidential models. For the purpose of algorithm development the
representaton of the model is not of much importantance. The models are
identified by their unique name (e.g. batch.gms).

The points

For a model in the GLOBALLib we will collect points. A point represent
some solution to a problem. The header of the file containing a point
explains the details of the point. It might contain the contributor of
the point, the solution value, the algorithm which was used to produce
the point, and the CPU time for finding the point. The points are part
of the library. They are indentified by the model name plus the
extension .p1, .p2, .p3, ... (e.g. ex4_1_1.p1).

In order to start a model from a certain point you can run gams in the
following way:

	  gams ex4_1_1 u1=ex4_1_1.p1

The controlling model globallib.gms

The library also contains the GAMS model globallib.gms that helps
organizing the models and points in the GLOBALLib. All models are
matched with propper references to contributors, publications, and
application areas.

The model also help to create batch execution scripts. For example. the
following piece of GAMS code creates a batch script that runs models that
come from the book "Handbook of Test Problems in Local and Global
Optimization" by Floudas e.a. with solver OQGRG :

file frs batch run script / rs.bat /;
  put frs "gams " " nlp=oqgrg dnlp=oqgrg cns=oqgrg " /;
  put$xp(m) xp.te(m);
  put /;