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arXiv · 2203.07022

Swap, Shift and Trim to Edge Collapse a Filtration

Marc Glisse·Siddharth Pritam
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Abstract

Boissonnat and Pritam introduced an algorithm to reduce a filtration of flag (or clique) complexes, which can in particular speed up the computation of its persistent homology. They used so-called edge collapse to reduce the input flag filtration and their reduction method required only the 1-skeleton of the filtration. In this paper we revisit the usage of edge collapse for efficient computation of persistence homology. We first give a simple and intuitive explanation of the principles underlying that algorithm. This in turn allows us to propose various extensions including a zigzag filtration simplification algorithm. We finally show some experiments to better understand how it behaves.

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Marc Glisse, Siddharth Pritam. 2022-03-14. Swap, Shift and Trim to Edge Collapse a Filtration. https://arxiv.org/abs/2203.07022

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