A filtered bucket-clustering method for projection onto the simplex and the \(\ell _1\) ball

  • Guillaume PerezEmail author
  • Michel Barlaud
  • Lionel Fillatre
  • Jean-Charles Régin
Short Communication Series A


We propose in this paper a new method processing the projection of an arbitrary size vector onto the probabilistic simplex or the \(\ell _1\) ball. Our method merges two principles. The first one is an original search of the projection using a bucket algorithm. The second one is a filtering, on the fly, of the values that cannot be part of the projection. The combination of these two principles offers a simple and efficient algorithm whose worst-case complexity is linear with respect to the vector size. Furthermore, the proposed algorithm exploits the representation of numeric values in digital computers to define the number of buckets and to accelerate the filtering.

Mathematics Subject Classification

49M30 65C60 65K05 90C25 



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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature and Mathematical Optimization Society 2019

Authors and Affiliations

  1. 1.Cornell UniversityIthacaUSA
  2. 2.Université Côte d’Azur, CNRSSophia AntipolisFrance

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