# Flexible Indexing of Repetitive Collections

@inproceedings{Belazzougui2017FlexibleIO, title={Flexible Indexing of Repetitive Collections}, author={Djamal Belazzougui and Fabio Cunial and Travis Gagie and Nicola Prezza and Mathieu Raffinot}, booktitle={Conference on Computability in Europe}, year={2017} }

Highly repetitive strings are increasingly being amassed by genome sequencing experiments, and by versioned archives of source code and webpages. We describe practical data structures that support counting and locating all the exact occurrences of a pattern in a repetitive text, by combining the run-length encoded Burrows-Wheeler transform (RLBWT) with the boundaries of Lempel-Ziv 77 factors. One such variant uses an amount of space comparable to LZ77 indexes, but it answers count queries…

## 10 Citations

### Indexing Highly Repetitive String Collections, Part I: Repetitiveness Measures

- Computer Science
- 2020

This survey describes the distinct compression paradigms that have been used to exploit repetitiveness, and the algorithmic techniques that provide direct access to the compressed strings.

### Indexing Highly Repetitive String Collections, Part II: Compressed Indexes

- Computer Science
- 2020

This survey covers the fundamental algorithmic ideas and data structures that form the base of all the existing indexes, and the various concrete structures that have been proposed, comparing them both in theoretical and practical aspects, and uncovering some new combinations.

### Indexing Highly Repetitive String Collections, Part I

- Computer ScienceACM Comput. Surv.
- 2022

This survey describes the distinct compression paradigms that have been used to exploit repetitiveness, and the algorithmic techniques that provide direct access to the compressed strings.

### Indexing Highly Repetitive String Collections

- Computer ScienceArXiv
- 2020

This survey describes the distinct compression paradigms that have been used to exploit repetitiveness, the fundamental algorithmic ideas that form the base of all the existing indexes, and the various structures that has been proposed, comparing them both in theoretical and practical aspects.

### Indexing Highly Repetitive String Collections, Part II

- Computer ScienceACM Comput. Surv.
- 2022

This survey covers the fundamental algorithmic ideas and data structures that form the base of all the existing indexes, and the various concrete structures that have been proposed, comparing them both in theoretical and practical aspects, and uncovering some new combinations.

### Resolution of the Burrows-Wheeler Transform Conjecture

- Computer Science2020 IEEE 61st Annual Symposium on Foundations of Computer Science (FOCS)
- 2020

This paper shows that r=\mathcal{O}(z\log^{2}n)$ holds for every text, and proves that many results related to BWT automatically apply to methods based on LZ77, and implies the first non-trivial relation between the number of runs in the BWT of the text and its reverse.

### Run Compressed Rank/Select for Large Alphabets

- Computer Science2018 Data Compression Conference
- 2018

By simple reductions to the colored predecessor problem, it is shown that the query times are optimal in the important case r ≥ 2logδ n, for an arbitrary constant δ > 0.

### Pangenomic Genotyping with the Marker Array

- Computer SciencebioRxiv
- 2022

A new method and software tool called rowbowt that applies a pangenome index to the problem of inferring genotypes from short-read sequencing data using a novel indexing structure called the marker array.

### Faster and Smaller Two-Level Index for Network-Based Trajectories

- Computer ScienceSPIRE
- 2018

This work proposes the use of a compact data structure on the bottom level of two-level indexes to handle trajectories of moving objects that are constrained to a network.

### Compressed Indexes for Repetitive Textual Datasets

- Computer ScienceEncyclopedia of Big Data Technologies
- 2019

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