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arXiv · 2201.00017

Fast ultrametric matrix-vector multiplication

Tobias Hofmann·Andy Oertel
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Abstract

We study the properties of ultrametric matrices aiming to design methods for fast ultrametric matrix-vector multiplication. We show how to encode such a matrix as a tree structure in quadratic time and demonstrate how to use the resulting representation to perform matrix-vector multiplications in linear time. Accompanying this article, we provide an implementation of the proposed algorithms and present empirical results on their practical performance.

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Tobias Hofmann, Andy Oertel. 2021-12-31. Fast ultrametric matrix-vector multiplication. https://arxiv.org/abs/2201.00017

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