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arXiv · 0802.1427

Approximating General Metric Distances Between a Pattern and a Text

Klim Efremenko·Ely Porat
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Abstract

Let $T=t_0 ... t_{n-1}$ be a text and $P = p_0 ... p_{m-1}$ a pattern taken from some finite alphabet set $Σ$, and let $\dist$ be a metric on $Σ$. We consider the problem of calculating the sum of distances between the symbols of $P$ and the symbols of substrings of $T$ of length $m$ for all possible offsets. We present an $ε$-approximation algorithm for this problem which runs in time $O(\frac{1}{ε^2}n\cdot \mathrm{polylog}(n,\absΣ))$

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Klim Efremenko, Ely Porat. 2008-02-11. Approximating General Metric Distances Between a Pattern and a Text. https://arxiv.org/abs/0802.1427

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