23.5.1 Major release (July 05, 2010)

Acknowledgments

We would like to thank all of our users who have reported problems and made suggestions for improving this release. In particular, we thank Farhad Farnam and Alexander Gocht.

GAMS System

APIs

• new VB.net example using GDX, Option and GAMS DLL: apifiles\examples\example2.vb
• combine Java api files in package com.gams.api, existing applications need to be adjusted when using the new Java api files, see e.g. apifiles\examples\example1.java:

    package com.gams.example1;
    import com.gams.api.*;
    public class example1 {
    ... 
  

Solvers

BARON

• New libraries 9.0.6

CONOPT

• New libraries 3.14U

CPLEX

• New libraries 12.2
• MIP kappa describes a new feature extending the computation of kappa to mixed integer programming (MIP). (In linear programming, kappa is also known as the condition number of a solution.) See GAMS/Cplex parameter mipkappastats for details.
• Intel processors prior to Pentium 4 are no longer supported.
• The MIP node log interval (GAMS/Cplex parameter MIPInterval) now accepts either a positive or negative integer value, making it easier for you to adjust the amount of information logged for your problem.
• The default value of the GAMS/Cplex ClockType parameter has changed from 0=automatic (let Cplex choose) to 2 (wallclock time).
• The concurrent optimizer launches distinct optimizers on multiple threads. Cplex now offers concurrent, deterministic optimization of linear programming models (LPs) when more than one thread is given to Cplex (GAMS/Cplex parameter Threads). Running concurrent optimizers simultaneously on multiple threads may consume more memory. If the memory reduction parameter (MemoryEmphasis) is turned on, then you have instructed CPLEX to conserve memory. In that case, Cplex does not run concurrent, deterministic optimization unless parameter LPMethod is explicitly set to 6.
• New parameter AuxRootThreads: Partitions the number of threads for Cplex to use for auxiliary tasks while it solves the root node of a problem. On a system that offers N processors or N global threads, if you set this parameter to n, where N > n > 0 then Cplex uses at most n threads for auxiliary tasks and at most N-n threads to solve the root node.

GUROBI

• New libraries 3.0.1
• Now also available on Mac OS X Intel 64bit

LINDOGLOBAL

• New libraries Lindo 6.1.1 for all platforms except for Solaris Sparc 32 bit and 64 bit
• Now also available on Mac OS X Intel 64bit

Model Libraries

GAMS Test Library

• gen_r1 (483): Generate GDX file for test of GDXMRW
• gen_r2 (484): Generate GDX file for test of GDXMRW
  
• gen_rbig (485): Generate GDX file for test of GDXMRW
• gdxmrw03 (486): test the Matlab utility rgdx
  
• gdxmrw04 (487): test the Matlab utility wgdx
• testinst (488): test the Matlab mex-file gams
• gversion (489): test the Matlab mex-file gams
• gdxmrw05 (490): test the Matlab mex-file gams
• onmulti7 (491): Test merge with $onmulti and empty data statement

Solver/Platform Availability Matrix

Solver/Platform availability - 23.5    July 4, 2010
	x86 MS Windows	x86_64 MS Windows	x86 Linux	x86_64 Linux	Sun Sparc SOLARIS	Sun Sparc64 SOLARIS	Sun Intel SOLARIS	IBM RS-6000 AIX 5.3	Mac Intel32 Darwin	Mac x86_64 Darwin	HP 9000 HP-UX 111	SGI IRIX2	DEC Alpha Digital Unix 4.03	Mac PowerPC Darwin4
ALPHAECP
BARON 9.0
BDMLP
COIN-OR
CONOPT 3
CPLEX 12.2											10.0	9.1	8.1
DECIS						32bit
DICOPT
GUROBI 3.0
KNITRO 6.0					5.2	32bit
LINDOGLOBAL 6.1					6.0	6.0
LGO
MILES
MINOS
MOSEK 6					5.0	5.0					3.2
MPSGE
MSNLP						32bit
NLPEC
OQNLP		32bit		32bit
PATH
SBB
SCIP
SNOPT
XA		32bit				32bit
XPRESS 20.00											16.10
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 Mac PowerPC is 23.3.

23.5.2 Maintenance release (August 18, 2010)

• AlphaECP: Fix for crash running under IDE
• API: Updated Python and Java APIs and examples
• Baron: Fixed issue with output formatting under Linux
• Baron: Memory leak when using BARON with external NLP solver
• Gdxmerge: Do not use path when checking for merged.gdx
• Gurobi: Fixed typo for option displayinterval
• McCarl Guide: Updates for 23.5
• Mosek 6 rev 85 libraries
• MPS2GMS: Removed mps2gms debug message
• Snopt: Fix for wrong return code (local,global)
• Xlsdump utility added