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arXiv · 1801.01404

String Periods in the Order-Preserving Model

Garance Gourdel·Tomasz Kociumaka·Jakub Radoszewski·Wojciech Rytter·Arseny Shur·Tomasz Waleń
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Abstract

The order-preserving model (op-model, in short) was introduced quite recently but has already attracted significant attention because of its applications in data analysis. We introduce several types of periods in this setting (op-periods). Then we give algorithms to compute these periods in time $O(n)$, $O(n\log\log n)$, $O(n \log^2 \log n/\log \log \log n)$, $O(n\log n)$ depending on the type of periodicity. In the most general variant the number of different periods can be as big as $\Omega(n^2)$, and a compact representation is needed. Our algorithms require novel combinatorial insight into the properties of such periods.

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Garance Gourdel, Tomasz Kociumaka, Jakub Radoszewski, Wojciech Rytter, Arseny Shur, Tomasz Waleń. 2018-01-04. String Periods in the Order-Preserving Model. https://arxiv.org/abs/1801.01404

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