Invited Session Fri.1.H 1058

Friday, 10:30 - 12:00 h, Room: H 1058

Cluster 10: Implementations & software [...]

Open source software for modeling and optimization


Chair: Theodore Ralphs



Friday, 10:30 - 10:55 h, Room: H 1058, Talk 1

Gus Gassmann
Optimization services: Connecting algebraic modelling languages to several solvers using a web-aware framework

Coauthors: Jun Ma, Kipp Martin


The common paradigm in mathematical optimization uses a modular approach consisting of an instance generator, e.g., an algebraic modelling language (AML), and a solver. Loosely coupled systems allow the substitution of one solver or AML for another. This is especially attractive when one considers open-source software, such as the suite of solvers that make up the COIN-OR project. However, the communication of solver options is an often overlooked detail. Solver developers often use options specific to their own solvers, and even where two solvers use the same option, syntax and interpretation may differ. This can be cumbersome, especially if the AML and solver reside on different computers. In addition, open-source solvers are often layered on top of other solvers, which adds to the complexity, since solver options may have to be directed at different levels in the solver hierarchy.
Optimization Services is a web-aware framework that provides a common interface between AMLs and a variety of open-source and commercial solvers. This talk explores some of the difficulties encountered in connecting the COIN-OR solver suite to a common AML, and the methods we used to overcome them.



Friday, 11:00 - 11:25 h, Room: H 1058, Talk 2

John Forrest
A bit of CLP (accelerated?)


With the availability of multi-core cpus, graphical processing units and new instructions, it may be time to revisit some ideas on accelerating the simplex method. This talk gives a progress report on a dual simplex code derived from COIN-LP designed to take advantage of new architectures.


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