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 23.3
|23.3.3||(Maintenance release)||December 17, 2009|
|23.3.2||(Maintenance release)||November 18, 2009|
|23.3.1||(Major release)||November 01, 2009|
GAMS Maintenance Release 23.3.3 - December 17, 2009
- MOSEK 6 rev 55 library with bug fixes
- 32bit HAR utilities available in 64bit Windows System
- Slow solution reporting in GAMS/Gurobi and other solvers fixed
GAMS Maintenance Release 23.3.2 - November 18, 2009
- Gurobi 2.0.1 library with bug fixes
- MOSEK 6 rev 53 library with bug fixes
- Updated CoinOS library with bug fixes
- Solver optfile bug fix in GAMSCHK
tolproj(1e-8) option for
GAMS Major Release 23.3.1 - November 01, 2009
We would like to thank all of our users who have reported problems and made suggestions for improving this release. In particular, we thank Wolfgang Britz, Wietse Dol, Daniel T. Fokum, Nuri Gokhan, Iiro Harjunkoski, Josef Kallrath, Lloyd R. Kelly, Kristina Konold, and Uwe Schneider.
- Assigning members to a set using the asterisk is now possible in decreasing order as well. For example, the following are valid set statements in GAMS.
Set years /bc2000*bc1,0*2009/; Set years /"-20"*"-1"/;
- The GAMS parameters
MaxProcDircan be used to control the generation of process directories.
ProcDir=abcwill use abc instead of the 225. The user is responsible to create and remove the directories.
%gams.procdir%will now be defined and give you the actual process directory in use.
MaxProcDir=100will extend the usual 225a to 225z, 225aa, 225ab, etc. The defaults will be 26 for
MaxProcDirand 225? for
ProcDirto make everything work as before.
- The GAMS parameter
- The Dollar Control Options
$hiddencalldoes the same as
$callbut makes sure that the statement is neither shown on the log nor the listing file. This is also true in case
$hiddencallis especially useful in case of an encrypted model that e.g. reads/writes from an password-protected Excel file using gdxxrw password option.
- Support of the Excel 2007 file extension xlsm
- The option
passwordallows to pass down a password to a protect Excel file
- New libraries: version 9.0
- Conopt can be used to solve nonlinear subproblems, but on 32bit platforms only (NLPSol=6)
- More control over common linear subexpressions
- CoinScip version 1.2
- The multi-commodity-flow network cut separator is now used by default
- Improvements in heuristics, presolving, and branching
- CoinGlpk version 4.39
- CoinCouenne version 0.2
- A separator for disjunctive cuts has been added
- CoinCplex, CoinGurobi, CoinMosek, CoinXpress
- These new bare bone solver links come free of charge with the GAMS Base system. General GAMS options (reslim, optcr, nodlim, iterlim) are supported. In addition an option file in the format required by the solver can be provided.
- CoinOS 2.0
- The new experimental link to the Optimization Services project allows you to convert instances of GAMS models into the OS instance language (OSiL) format and to let an Optimization Services Server solve your instances remotely.
- New libraries: version 2.0
- Simplex performance: The simplex optimizers are much faster in the release. The improvements are most pronounced in the dual simplex method.
- MIP performance: The MIP solver is significantly faster as well. Part of this is a consequence of the increased speed of the dual simplex optimizer, and part is due to algorithmic improvements in the MIP itself.
- MIP IIS: You can now compute an Irreducible Inconsistent Subsystem (IIS) for an infeasible MIP model. The previous release could only compute IISs for continuous models.
- MIP node files: You can now store search tree nodes on disk. This allows you to solve much larger and more difficult MIP models. Use the new NodefileStart parameter to indicate how much memory you would like to devote to nodes before they are written to disk. The performance impact of putting nodes out to disk is typically quite small.
MINOS5 (old version of MINOS) was dropped. MINOS5 now is an alias to MINOS (Version 5.51) in order to protect users that hard-coded the use of MINOS5.
- New libraries: version 6.0
- Improvement of speed and stability of the interior-point optimizer for linear and conic problems
- More effective presolve for simplex optimizer with hot starts
- New libraries: version 20.00
- Updated licensing: multi-threaded runs and 64-bit versions now included in base license
threadsoption allows specification of cores left free for non-XPRESS work.
- Lindoglobal supports in-core communication
transxls (74): Solve classical transportation problem in Excel, using vba API (gamsx, opt and gdx)
negishi (21): Pure exchange model solved with EMP, SJM, and CGE
set10 (449): first entry in set/param data has wrong dimension
set11 (450): test for order when using set.id or set#id or #id
gdxcopy5 (451): Test GDX environment variables with trailing blanks
ifthen2 (452): Test nested $ifthen and $endif
ifthen3 (453): Test $ifthen $elseif/else $endif
ifthen4 (454): Tests $ifthen from old release notes
eval01 (455): constant evaluation with non-stop arithmetic
eval02 (456): $eval/ife/... sameas function
forceerr (457): ForceError and ForceErrorCnt Example
gdxxrw5 (458): Test for password handling of gdxxrw and $hiddencall
lolp (459): LP Test for logoption
lonlp (460): NLP Test for logoption
lomcp (461): MCP Test for logoption
eval03 (462): test constant compile time evaluation functions
eval04 (463): test constant compile time evaluation operators
|Solver/Platform availability - 23.3 November 1, 2009|
Digital Unix 4.03
|1)GAMS distribution for HP 9000/HP-UX is 22.1.|
|2)GAMS distribution for SGI IRIX is 22.3.|
|3)GAMS distribution for DEC Alpha is 22.7.|
|4)GAMS distribution for IBM RS-6000 AIX 4.3 is 23.1.|