Release 11.4 (January 2016)

Release 11.4 includes fixes for several smaller bugs detected during the last year, and it offers several speed-ups, both at compile time (LTG) and at runtime.

The table below compares GEMPACK 11.4 compile times (LTG) and model runtimes with those for the previous 11.3 version. We list results for GTAP (which is LU-bound) and MMRF (where non-LU operations dominate runtime). Results are shown for the Intel, GFortran and Lahey/Fujitsu compilers, in each of 32-bit and 64-bit versions where supported. Runtimes are reported for both GEMSIM and Tablo-generated exes.

GEMPACK 11.4 and 11.3 compile times (LTG) and runtimes in seconds

GP 11.4/11.3 times compared

Tests were run on a desktop PC running Windows 7 64-bit with an (quad-core) Intel i7-4770 CPU, 32 GB memory and 512 GB SSD hard drive. Compilers were: GFortran 4.8.1, Intel Fortran 14.0 and Lahey/Fujitsu Fortran 7.2 professional.

A more comprehensive compiler comparison is available on our supported Fortran compilers page.

The table shows striking reductions in LTG times, and useful runtime speedups for LU bound models represented here by the GTAP model. Also noteworthy, free GFortran is marginally faster than Intel Fortran for the Tablo-generated executable program implementation of MMRF.


Release 11.4 will be supplied to all new GEMPACK purchasers. Current subscribers to the annual payment scheme for the source-code version of GEMPACK are advised to download a free upgrade -- they should email (specifying their licence number) for further details.

Advice to GFortran source-code users

Note that GEMPACK 11.4 or later requires GFortran version 4.8.1 (it actually fails to compile with the older GFortran 4.5). If upgrading to GFortran version 4.8.1, first uninstall the older GFortran. [In Control Panel "Programs and Features" uninstall "MinGW-w64 version 1.0 GCC 4.5.4 prerelease (GEMPACK compatible)". More information.]

Advice to Intel Fortran source-code users

EXE files produced by GEMPACK 11.4 and the Intel compiler need to have access to a file called libiomp5md.dll. Normally access is guaranteed, since this file comes with both GEMPACK 11.4 and Intel Fortran. However, if you use GEMPACK 11.4 (or later) with Intel Fortran and intend to distribute TABLO-generated EXE files (for example, in RunDynam archives or in RunGTAP version zips) to other people who might not have installed Intel Fortran or GEMPACK 11.4, you should be aware of the missing DLL problem.

See also:
Improvements for GEMPACK Release 11.3 (Jun 2014, January 2015)
Improvements for GEMPACK Release 11.2 (May 2013)
Improvements for GEMPACK Release 11.1 (May 2012)
New features of GEMPACK Release 11.0 (October 2011)
Improvements for GEMPACK Release 10.0-001 (April 2009)
All GEMPACK release notes
Different versions of GEMPACK