Xpress-Optimizer의 특징은 정교하고 최신식의 알고리즘을 통해 산업에서 요구하는 문제들을 빠르고 정확하게 해결합니다. Optimization 기술은 세계 각국의 다양한 분야의 기업들에게 수백만 개의 변수와 제약조건을 가진 문제들에 대하여 빠르고 안정적인 Solution을 제공함으로써 이미 검증되었습니다.

Xpress-Optimizer는 계산상 어렵고 불안정한 문제를 해결하는 능력을 갖고 있는 것으로 잘 알려져 있으며, 이것은 프로세스 산업에서 시장의 리더가 되는 이유 중 하나입니다.

Cutting-edge Algorithms

Xpress-Optimizer 알고리즘은 사용자가 다음과 같은 문제를 풀수 있습니다 :

• LP - Linear programming problems
• MIP - Mixed integer programming problems
• QP - Quadratic programming problems
• MIQP - Mixed integer programming problems
• QCQP - Quadratically constrained quadratic problems
• MIQCQP - Quadratically constrained mixed integer problems
• NLP - Convex non-linear problems

만약 non-linear 혹은 non-convex 문제를 해결해야 한다면 , 수천개의 변수를 가진 non-linear와 mixed integer non-linear 문제를 풀 수 있는 Xpress-SLP solver를 통하여 해결하실 수 있습니다.

Flexible Deployment

The Xpress-Optimizer is available as a command-line tool with a simple yet powerful interactive user interface and as a callable library with C, C++, Java, Fortran, VB6 and .NET programming interfaces. It is fully compatible with the industry-standard LP and MPS file formats and has extensive support for logging, binary save/basis files and ASCII/binary solution files.

As an integrated component of the Xpress-MP suite, the advanced model development environment of Xpress-Mosel or the extensive programming functionality of the Xpress-BCL model-building library can also be used to interact with the raw power and performance of the Xpress-Optimizer engine.

Cross-Platform

The Xpress-Optimizer is available for a wide variety of architectures and operating systems and is enhanced to take advantage of individual platform characteristics.

The Simplex Optimizer

The Xpress-Optimizer provides fast, reliable implementations of the primal and dual simplex methods for solving LP problems.

• Integrated presolve algorithm to reduce problem size and solve time
• Automatic settings for best performance and an extensive range of user-configurable parameters for advanced control of the optimization process.
• Fast restarts from an existing advanced basis. Problems can be modified and then resolved in a fraction of the original solution time
• Infeasibility detection and diagnostics for tracing problem infeasibilities
• Effective degeneracy resolution techniques

The Barrier Optimizer

The Xpress-Optimizer Barrier algorithm provides an alternative to the simplex algorithms and uses interior point methods to solve both linear programming and quadratic programming problems.

• Integrated presolve algorithm to reduce problem size and solve time
• Cutting edge Cholesky factorization algorithms
• Fast primal and dual crossover to basic solutions
• Dense column handling
• Solutions available without crossover
• Available as Parallel Barrier for multi-processor machines on specific platforms

The MIP Optimizer

The Xpress-Optimizer uses a sophisticated branch and bound algorithm to solve MIP and MIQP problems and is well known for its ability to quickly find high quality solutions.

• MIP presolve algorithm pre-processes the problem to reduce problem size and solve time
• Advanced cutting-plane strategies to automatically improve the quality of bounds and reduce the size of the global search
• Flow covers
• GUB covers
• Lift and Project
• Clique cuts
• Flow paths
• Mixed integer rounding
• Gomory fractional cuts
• Binary, integer and semi-continuous variables, and special ordered sets
• Breadth-first, best-first or depth-first search. Customizable node and variable selection strategies. User callbacks allow complete control over the node and variable selection
• Multiple LP algorithms for initial LP relaxation and node solution
• User-defined branching priority and branch direction directives
• Heuristics
• Available as Parallel-MIP for multi-processor machines on specific platforms