International Conference Papers
Permanent URI for this collectionhttp://dl.cerist.dz/handle/CERIST/4
Browse
3 results
Search Results
Item Flexible Indexing of Repetitive Collections(Springer, 2017-06-07) Belazzougui, Djamal; Cunial, Fabio; Gagie, Travis; Prezza, Nicola; Raffinot, MathieuHighly 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 count- ing 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 vari- ant uses an amount of space comparable to LZ77 indexes, but it answers count queries between two and four orders of magnitude faster than all LZ77 and hybrid index implementations, at the cost of slower lo- cate queries. Combining the RLBWT with the compact directed acyclic word graph answers locate queries for short patterns between four and ten times faster than a version of the run-length compressed suffix ar- ray (RLCSA) that uses comparable memory, and with very short pat- terns our index achieves speedups even greater than ten with respect to RLCSA.Item Fully Dynamic de Bruijn Graphs(Springer International Publishing, 2016-09-21) Belazzougui, Djamal; Gagie, Travis; Mäkinen, Veli; Previtali, MarcoWe present a space- and time-efficient fully dynamic implementation of de Bruijn graphs, which can also support fixed-length jumbled pattern matching.Item Bidirectional Variable-Order de Bruijn Graphs(Springer International Publishing, 2016-03-22) Belazzougui, Djamal; Gagie, Travis; Mäkinen, Veli; Previtali, Marco; Puglisi, Simon J.Implementing de Bruijn graphs compactly is an important problem because of their role in genome assembly. There are currently two main approaches, one using Bloom filters and the other using a kind of Burrows-Wheeler Transform on the edge labels of the graph. The second representation is more elegant and can even handle many graph-orders at once, but it does not cleanly support traversing edges backwards or inserting new nodes or edges. In this paper we resolve the first of these issues and partially address the second.