Section: New Software and Platforms

Comparing Continuous Optimizers (Coco) Platform

Participants : Dimo Brockhoff, Arnaud Liefooghe, Thanh-Do Tran.

The Coco Platform (coco.gforge.inria.fr ) provides the functionality to automatically benchmark optimization algorithms for unbounded, unconstrained optimization problems in continuous domains. Benchmarking is a vital part of algorithm engineering and a necessary path to recommend algorithms for practical applications. The Coco platform releases algorithm developers and practitioners alike from (re-)writing test functions, logging, and plotting facilities by providing an easy-to-handle interface in several programming languages. The Coco platform has been developed since 2007 and has been used extensively within the “Blackbox Optimization Benchmarking (BBOB)” workshop series since 2009. Overall, 123 algorithms and algorithm variants by contributors from all over the world have been benchmarked with the platform so far and all data is publicly available for the research community (see for example http://coco.gforge.inria.fr/doku.php?id=bbob-2013-algorithms for the submissions to BBOB-2013).

Via the ANR project NumBBO, also Dolphin team members are involved in the development of Coco and it is one of the main purposes of NumBBO to extend the Coco platform towards expensive, large-scale, constrained and multiobjective optimization. In order to facilitate these extensions, a complete overhaul of the platform is currently underway—rewriting the whole functionality from scratch in a single language (ANSI C) which will then be called from all other provided languages (Java, python, Matlab/Octave, R) instead of multiple independent implementations which are highly difficult to maintain. A first release of the new code base is expected in the first half of 2015.

For the rewriting of the source code, we also moved to a publicly available open source code repository at https://code.google.com/p/numbbo/ which, in addition, provides for the first time a bug and feature request tracking system for Coco. As the first Coco-related deliverable of the NumBBO project, the extension towards expensive optimization has been finished this year. Its full functionality will be provided for the first time for the upcoming BBOB special session at the IEEE Congress on Evolutionary Computation (CEC'2015). Coco is also currently extended towards multiobjective optimization in close relation to the PhD topic of Thanh-Do Tran. A first working (but still preliminary) version of the multiobjective Coco has been developed and is expected to be merged with the newly rewritten Coco code just after its first release.

Inria software self-assessment for Coco: [A-4/5, SO-4, SM-3-up4, EM-3, SDL-4-up5][DA-3, CD-3, MS-3, TPM-2]