Editing CPLEX (section)

== Release history ==
Prior to IBM acquiring ILOG, the CPLEX team published a release history of CPLEX.<ref name="CPLEXHistory">{{cite web|title=CPLEX History|url=http://www.ilog.com/products/cplex/news/history.cfm|archive-url=https://web.archive.org/web/20090413054926/http://www.ilog.com/products/cplex/news/history.cfm|url-status=dead|archive-date=13 April 2009|website=CPLEX History as published by ILOG |accessdate=24 June 2020}}</ref>
<br />
{| class="wikitable"
|+
! Version
! Release Date
! Key Features
|-
| 22.1.1
| December, 2022
| Python 3.7 support dropped, new solver parameter added.<ref name="Release notes 22.1.1">{{cite web|title=Release notes for CPLEX 22.1.1|url=https://www.ibm.com/docs/en/icos/22.1.1?topic=2211-release-notes-cplex|accessdate=11 January 2023|archive-date=11 January 2023|archive-url=https://web.archive.org/web/20230111074516/https://www.ibm.com/docs/en/icos/22.1.1?topic=2211-release-notes-cplex|url-status=live}}</ref>
|-
| 22.1.0
| March, 2022
| Python 3.9 and 3.10 support added, new solver parameters added.<ref name="Release notes 22.1.0">{{cite web|title=Release notes for CPLEX 22.1.0|url=https://www.ibm.com/docs/en/icos/22.1.0?topic=2210-release-notes-cplex|accessdate=11 January 2023}}</ref>
|-
| 20.1
| December, 2020
| MIP performance improvements, new 'emphasis MIP 5' mode, etc.<ref name="Release notes">{{cite web|title=CPLEX 20.1 Release Notes|url=https://www.ibm.com/support/knowledgecenter/SSSA5P_20.1.0/ilog.odms.studio.help/CPLEX/ReleaseNotes/topics/releasenotes201/home.html|accessdate=4 March 2021}}</ref>
|-
| 12.10
| December, 2019
| MIP performance improvements and the addition of a generic branching callback to the other generic callbacks introduced in version 12.8.
|-
| 12.9
| March, 2019
| Direct support for multiobjective optimization, callback functionality improvement.
|-
| 12.8
| December, 2017
| Generic callback, API recorder to facilitate debugging, subMIP control parameters, Download and Go offering.
|-
| 12.7
| November, 2016
| Automated Benders decomposition, modeling assistance tool, runseeds command to better assess performance variability.
|-
| 12.6.2
| June, 2015
| Performance improvements (mainly for SOCP, MISOCP, non-convex QP), support for cloud based optimization.
|-
| 12.6
| December, 2013
| Support for nonconvex QPs and MIQPs, distributed parallel MIP and more parallelism at the root node for MIPs..
|-
| 12.5
| October, 2012
| MIP performance improvements, random seed parameter to address performance variability, remote object, duals for QCPs, deterministic tuning tool.
|-
| 12.4
| November, 2011
| Deterministic time limit support, duals for SOCPs, quadratic expression API in Concert, performance improvements across all algorithms, but especially MIP.
|-
| 12.3
| June, 2011
| Support for large nonzero counts that require 64 bit indexing, local optima for non-convex QP, and globalization.
|-
| 12.2
| June, 2010
| More parallelism at the root node, deterministic parallel concurrent LP optimization, along with some additional barrier performance improvements and additional tools for diagnosing ill conditioned basis matrices in MIPs.
|-
| 12.0
| April, 2009
| The first version after IBM acquired ILOG.  Includes connectors for Python, MATLAB and Excel.  Deterministic parallel barrier is also included.
|-
| 11.0
| October, 2007
| Breakthrough performance gains for mixed integer programming (MIP) models and enhanced parallel MIP optimization. The MIP solution pool feature and the performance tuning utility are introduced.
|-
| 10.0
| January, 2006
| Performance improvements in the primal simplex and barrier methods, as well as the MIP optimizer. Indicator constraints and solution polishing heuristics are introduced and improvements to infeasibility analysis are made.
|-
| 9.0
| December, 2003
| Performance improvements in primal and dual simplex methods and the MIP optimizer. It includes ILOG Concert Technology for .NET users and support for quadratically constrained programs.
|-
| 8.0
| July, 2002
| MIP performance improvements and support for mixed integer quadratic programs.
|-
| 7.5
| December, 2001
| ILOG Concert Technology for Java users.
|-
| 7.0
| October, 2000
| ILOG Concert Technology for C++ users.
|-
| 6.5
| March, 1999
| Significant performance improvements in primal and dual simplex methods, and ILOG CPLEX Mixed Integer Optimizer.
|-
| 6.0
| April, 1998
| Significant performance improvements in primal and dual simplex methods, and CPLEX Barrier Optimizer.
|-
| 5.0
| September, 1997
| New memory model for easy C++ integration.
|-
| 4.0.5
| March, 1996
| Parallel CPLEX Mixed Integer Solver is introduced.
|-
| 4.0
| December, 1995
| Redesigned advanced programming interface (API) to allow thread-safe applications.
|-
| 3.0.8
| March, 1995
| Parallel CPLEX Barrier Solver is introduced.
|-
| 3.0
| April, 1994
| CPLEX Barrier Solver is introduced.
|-
| 2.1
| March, 1993
| Introduction of CPLEX Presolve algorithms.
|-
| 2.0
| April, 1992
| Performance improvements.
|-
| 1.2
| 1991
| Support for the dual simplex method and CPLEX Mixed Integer Optimizer.
|-
| 1.0
| 1988
| Primal Simplex Method
|}