Computers GEMPACK Runs On

Most GEMPACK modellers use some version of the Windows operating system (often a 64-bit version of Windows 7 or later).

In previous times , when Windows PCs were less powerful, some people ran large GEMPACK models on mainframe or mini- computers, while preparing input files and viewing results on a Windows PC. Disadvantages included: the need for users to master the OS (often UNIX) of the remote machine; and the inconvenience of constantly copying input and result files between the two systems (often requiring file format conversions).

Today's PCs are much more powerful, and with 64-bit Windows are able to solve very large models. Consequently, the number of non-Windows GEMPACK users has become small. We still offer, by special arrangement, a Linux/Unix edition of the Source-code Version of GEMPACK, but would urge users to consider the Windows alternatives.

Nevertheless GEMPACK can be used in a non-Windows environment, such as Linux or MacOSX. To understand the issues involved, we must distinguish between two main types of GEMPACK program:

Command-line, Fortran-based programs: Core command-line [non-GUI] programs, such as TABLO and GEMSIM, are written in Fortran, and could in principle be compiled and run natively on any computer with a standard Fortran compiler. Included in this group are the TABLO-generated model-specific EXE files created with Source-code GEMPACK.

Visual [GUI] programs: Programs such as ViewHAR, TABmate, AnalyseGE are created as Windows programs using the Delphi compiler. So none of these very useful programs can run natively under a non-Windows OS such as Linux or MacOSX. The solutions to this problem are of three main types:

  1. Dual boot systems, such as BootCamp on the Mac, let you simply reboot the machine into Windows.
  2. Virtual machines, such as Parallels, VirtualBox or VMWare Fusion let you launch a Windows session from within your MacOSX or Linux session.
  3. WINE-based systems, like Crossover, provide software libraries that allow a Windows program to run within Linux/MacOSX.

Methods 1 and 2 (but not 3) require that you purchase your own copy of Windows. Methods 2 and 3 often require some tinkering to make particular Windows programs run smoothly. You can choose between paid and free versions of 2 or 3 -- you might need to tinker less if you pay. You need to research on-line before deciding.

GEMPACK on the Mac

The executable-image version of GEMPACK (which includes several Windows GUI programs) has been installed on Macs using all three of the methods listed above. In particular we have heard (but not seen) that GEMPACK runs well on the Windows virtual sessions provided via Parallels. WINE/Crossover has also been used. One person completed a GEMPACK training course using Bootcamp on a Mac with the Executable-Image Version of GEMPACK.

Recent Macs, using Intel CPUs and the OS X operating system, may be used in conjunction with a Mac Fortran compiler to run native Mac versions of command-line [non-GUI, Fortran-based] GEMPACK programs.

GEMPACK on Linux

A Linux version of GEMPACK Release 8 was prepared -- but attracted little interest. Read more here. More recently, people have experimented with running GEMPACK under WINE/Ubuntu, with some success.

Fortran file formats

Historically, each Fortran compiler used its own idiosyncratic format for binary files (such as HAR files). To share data with others, a special text interchange format was needed. GEMPACK still provides programs (RWHAR, MKHAR,RWSOL and MKSOL) to translate its binary files to and from text format.

Fortunately, it seems that most Fortran compilers for the x-86 CPUs (used by most Windows, Mac and Linux PCs) now have converged on the same format. This assists inter-operability.