With the Demonstration Version and the Executable-Image Version of GEMPACK, the program GEMSIM is used to run simulations.
However there is another way of implementing models in which the program TABLO is used to convert the algebraic equations of the economic model into a Fortran program (referred to as a TABLO-generated program) specific to that model. The Fortran TABLO-generated program is compiled and linked to a library of GEMPACK subroutines. The executable image produced is used to run simulations on the model (instead of using GEMSIM). This method provides faster execution times for large models but means that you must have an appropriate Fortran compiler.
With a Source-code version of GEMPACK, either GEMSIM or TABLO-generated programs can be used for simulations, though usually the TABLO-generated program is preferred for large models since it runs more quickly.
A full GEMPACK licence (that is, a Source-code licence) includes the full Fortran source code for all programs and subroutines.