## Using branching-property preserving Pruefer Code to encode solutions for Particle Swarm Optimization

### Hanno Hildmann, Dymitr Ruta, Dina Y. Atia, A. F. Isakovic

DOI: http://dx.doi.org/10.15439/2017F117

Citation: Proceedings of the 2017 Federated Conference on Computer Science and Information Systems, M. Ganzha, L. Maciaszek, M. Paprzycki (eds). ACSIS, Vol. 11, pages 429–432 (2017)

Abstract. In the area of applied optimization, heuristics are a popular means to address computational problems of high complexity. Modeling the problem and mapping all variations of its solution into a so-called solution space is an integral part of this process. Representing solutions as graphs is common and, for a special type of graph, Pruefer Code (PC) offers a computationally efficient (algorithms of O(n)-complexity are known) mapping to n-2 dimensional Euclidean space. However, this encoding does not preserve properties such as e.g. locality and therefore PC has been shown to be a bad choice for entire classes of problems. We argue that Pruefer Code does allow the preservation of some properties (e.g. degree of branching and branching vertices) and that these are sufficiently relevant for certain types of problems to motivate encoding them in PC. We present our investigations and provide an example where PC has been shown to be a useful encoding.

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