IBM ILOG CPLEX is the best known and most widely used large-scale solver. Its efficiency and robustness have been demonstrated over two decades in thousands of commercial installations worldwide.
Developer: IBM ILOG
Current version: 12.6.3
Problem types supported: Linear and quadratic optimization in continuous and integer variables. Support is provided for both convex and nonconvex quadratic objectives, and for convex quadratic constraints.
Special forms detected: Logical implications in the form of “indicator” constraints. Convex quadratic expressions in objectives, and convex quadratic constraints of elliptic and conic types.
Algorithms available: For continuous problems, primal and dual simplex, interior-point (barrier); for integer problems, advanced branch-and-bound with presolve, feasibility heuristics, and cut generators. For continuous problems comprised mostly or entirely of linear network flow constraints, network simplex.
Special features: Shared-memory parallel processing for barrier, branch-and-bound. Concurrent optimization by several methods to determine best choice. Special facilities for parameter tuning and infeasibility diagnosis.
See also: ILOG CP for AMPL, covered by the CPLEX for AMPL license, for access to constraint programming and more general CPLEX handling of logical constraints.
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