Major releases contain substantial changes to the GAMS system. The License Check date is set to the release date of the major release.
Minor releases are mainly issued to provide bug fixes, performance improvements, and maintenance releases of solver libraries. Additionally, they can provide a few new features that do not change existing behavior. The License Check Date remains the same as for the prior major release. This means that any license file that worked with the prior major release will also work with this minor release.
Maintenance releases do not provide any new features. They are issued to provide bug fixes, performance improvements, and maintenance releases of solver libraries. The License Check Date remains the same as for the prior major release. This means that any license file that worked with the prior major release will also work with this maintenance release.
GAMS Distribution 22.6 - December 24, 2007
This is a Major release.
AcknowledgementsWe would like to thank all of our users who have reported problems and made suggestions for improving this release. In particular, we thank Anton Eremeev, Michael Ferris, Christian Gilow, Uwe Schneider, Monique Guignard-Spielberg and Stefan Vigerske.
- Solaris on Sparc64 (64-bit)
- Mac on Intel (32-bit)
- Complete detailed GAMS Release Notes
- Dollar Control Options
- $ifthen, $elseif, $else and $endif
- $eval, $evallocal and $evalglobal
- Syntax for Constant Evaluation
- Additional Licensing Information
- Put Writing Facility
- Enhanced Functions on controlling Sets
- Other Enhancements
- Unlimited input string length for $call, execute and put_utility exec/shell.
- The listing file can be redirected to the standard error stream by using the gams parameter ao=3
- The model attribute
.numvarproj was added to count bound projections during model generation. Some minor additions to MODEL STATISTICS and an enhanced column listing help identify potential problems (the variable attribute .infeas could also be used to display potential bound projections)
- GAMS IDE:
- GDXviewer supports Excel 2007 format xlsx
- GDXviewer has an integrated symbol search
- GAMS Model library: New models
- Asynchronous Jacobi Methods (jacobi)
- Dantzig Wolfe Decomposition and Grid Computing (danwolfe)
- Portfolio Modeling with Parallel Solutions (qmeanvag)
- Cplex Solution Pool for a Simple Facility Location Problem (solnpool)
- Mission Planning for Synthetic Aperture Radar Surveillance (swath)
- TSP tour plotting with LaTeX xy-pic environment (tsp2ltx)
- Min Cost Flow with an Instance generated by NETGEN (netgen)
- Supports Excel 2007 format xlsx
- GAMS distributes and supports utilities for converting HAR (header array) files used by GEMPACK: gdx2har and har2gdx. Details about these utilities can be found at Tom Rutherford's page here.
- AlphaECP:New libraries (version 1.63).
AlphaECP can call an NLP solver during the optimization to improve
convergence properties for continuous variables.
- BARON:New libraries (version 8.1.1).
XPRESS is available as a subsolver for LPs (option "lpsol=7").
Identification of common linear subexpressions in nonlinear functions
that speeds up BARON's parsing time considerably for certain problems.
- COIN-OR Solvers:New solver libraries of
CBC/CLP (2.0), GLPK (4.22), IPOPT (3.3), BONMIN (0.9). The GAMS/CoinCBC
link has been completely rewritten so that it offers the performance of
the CBC standalone version. Many new options have been added. The
GAMS/CoinGLPK link uses now the advanced B&B solver of GLPK.
Support of Solaris 64bit Intel platform (SIG) and Mac OS on Intel chips
- CPLEX:New libraries (11.0). There are
quite a few changes in Cplex 11 and the GAMS/CPLEX interface. Please
check the detailed GAMS/CPLEX 11 release
notes. The major enhancements are:
- Improved Mixed Integer Programming (MIP) Performance
- Enhanced Parallel MIP
- Multiple MIP Solutions
- Performance Tuning tool
- LINDOGLOBAL:New libraries (version
184.108.40.206). Support of Solaris Sparc64 platform (SOX) and Intel Mac
- MOSEK:New libraries (version 220.127.116.11).
Support of Solaris Sparc64 platform (SOX) and Mac OS on Intel chips
- XPRESS:New libraries (version 18.00)
|Solver/Platform availability - 22.6 December 24, 2007|
Digital Unix 4.0
|1)GAMS distribution for HP 9000/HP-UX is 22.1.|
|2)GAMS distribution for SGI IRIX is 22.3.|