Title
Irredundant tandem motifs
Abstract
Eliminating the possible redundancy from a set of candidate motifs occurring in an input string is fundamental in many applications. The existing techniques proposed to extract irredundant motifs are not suitable when the motifs to search for are structured, i.e., they are made of two (or several) subwords that co-occur in a text string s of length n. The main effort of this work is studying and characterizing a compact class of tandem motifs, that is, pairs of substrings occurring in tandem within a maximum distance of d symbols in s, where d is an integer constant given in input. To this aim, we first introduce the concept of maximality, related to four specific conditions that hold only for this class of motifs. Then, we eliminate the remaining redundancy by defining the notion of irredundancy for tandem motifs. We prove that the number of non-overlapping irredundant tandem motifs is O(d^2n) which, considering d as a constant, leads to a linear number of tandems in the length of the input string. This is an order of magnitude less than previously developed compact indexes for tandem extraction. The notions and bounds provided for tandem motifs are generalized for the case r=2, if r is the number of subwords composing the motifs. Finally, we also provide an algorithm to extract irredundant tandem motifs.
Year
DOI
Venue
2014
10.1016/j.tcs.2013.08.012
Theor. Comput. Sci.
Keywords
DocType
Volume
Irredundant tandem motif,irredundant motif,text string,compact class,length n,irredundant tandem motif,tandem motif,input string,compact index,tandem extraction,linear number
Journal
525,
ISSN
Citations 
PageRank 
0304-3975
3
0.41
References 
Authors
0
3
Name
Order
Citations
PageRank
Laxmi Parida177377.21
Cinzia Pizzi213915.73
Simona E. Rombo319222.21