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On the Expected Sublinearity of the Boyer–Moore Algorithm

R. Schaback
1988 SIAM journal on computing (Print)  
This paper analyzes the expected performance of a simpli ed version BM 0 of the Boyer{Moore string matching algorithm.  ...  Formal developments lead then to the conclusion that A takes expected sublinear time in a variety of situations.  ...  The sublinearity (i.e. the expected number of character comparisons is less than N) was proved in the original paper 2] by Boyer and Moore, while Knuth, Morris, and Pratt 6] gave a variation with expected  ... 
doi:10.1137/0217041 fatcat:i6yfd4fuyjhkxl37xxe32ldp3i

Fast parameterized matching with q-grams

Leena Salmela, Jorma Tarhio
2008 Journal of Discrete Algorithms  
The problem of finding all parameterized matches of a pattern in a text has been studied in both one and two dimensions but the research has been centered on developing algorithms with good worst-case  ...  We present algorithms that solve this problem in sublinear time on average for moderately repetitive patterns.  ...  Three one-dimensional algorithms Our one-dimensional algorithms are derived from the Horspool variant of the Boyer-Moore algorithm. In the BMH algorithm the text is processed in windows of size m.  ... 
doi:10.1016/j.jda.2007.11.001 fatcat:ex5t4qmstfanrpfzm4egbbf6ku

Page 4650 of Mathematical Reviews Vol. , Issue 89H [page]

1989 Mathematical Reviews  
(D-GTN-N) On the expected sublinearity of the Boyer-Moore algorithm. SIAM J. Comput. 17 (1988), no. 4, 648-658.  ...  This paper analyzes the expected performance of a simplified ver- sion, BM’, of the Boyer-Moore string-matching algorithm.  ... 

Approximate Boyer–Moore String Matching

Jorma Tarhio, Esko Ukkonen
1993 SIAM journal on computing (Print)  
Our generalized Boyer-Moore algorithm is shown (under a mild independence assumption) to solve the problem in expected time O(kn( 1 m -k + k c )) where c is the size of the alphabet.  ...  Both algorithms are functionally equivalent with the Horspool version of the Boyer-Moore algorithm when k = 0.  ...  Acknowledgement Petteri Jokinen performed the experiments which is gratefully acknowledged.  ... 
doi:10.1137/0222018 fatcat:pbbjsiuqpvf3rdnphzci3kcdq4

Multipattern string matching withq-grams

Leena Salmela, Jorma Tarhio, Jari Kytöjoki
2007 ACM Journal of Experimental Algorithmics  
We ran extensive experiments with them and compared them with various versions of earlier algorithms, e.g. different trie implementations of the Aho-Corasick algorithm.  ...  All of our algorithms showed to be substantially faster than earlier solutions for sets of 1,000-10,000 patterns and the good performance of two of them continues to 100,000 patterns.  ...  [Baeza-Yates 1989; Boyer and Moore 1977] ) that the use of q-grams can increase the average length of shift in the algorithms of Boyer-Moore type.  ... 
doi:10.1145/1187436.1187438 fatcat:mcvl65aa4bbjlaceyqiu4qmb5i

Approximate Online Matching of Circular Strings [chapter]

Tommi Hirvola, Jorma Tarhio
2014 Lecture Notes in Computer Science  
Recently a fast algorithm based on the BNDM algorithm has been presented for exact matching of circular strings.  ...  From this algorithm, we derive several sublinear methods for approximate online matching of circular strings. The applicability of the new algorithms is demonstrated with practical experiments.  ...  Superficially BNDM appears to be a cross of the Shift-Or and Boyer-Moore algorithms [3] .  ... 
doi:10.1007/978-3-319-07959-2_27 fatcat:ubtjowdobbfqxe26qe7czxnkke

Page 3734 of Mathematical Reviews Vol. 58, Issue 5 [page]

1979 Mathematical Reviews  
(the Boyer-Moore algorithm is known to be sublinear on the aver- age).”  ...  Therefore there do not exist pattern matching algorithms whose worst-case behavior is ‘sublinear’ in n (that is, linear with constant less than one), in contrast with the situation for average behavior  ... 

A variation on the Boyer-Moore algorithm

Thierry Lecroq
1992 Theoretical Computer Science  
Acknowledgment I thank Wojciech Rytter for an interesting discussion on this subject.  ...  Comparison with the Boyer-Moore algorithm on few examples Intuitively, one can expect a better behavior of Algorithm 3 (A3) than of Boyer-Moore algorithm (BM).  ...  Section 8 introduces Boyer-Moore automaton and presents the automaton based on our strategy. Section 9 compares the Boyer-Moore algorithm with ours on the basis of some examples.  ... 
doi:10.1016/0304-3975(92)90139-7 fatcat:4djltb7kofgqtgpwnhtp3xu4um

Page 2945 of Mathematical Reviews Vol. , Issue 95e [page]

1995 Mathematical Reviews  
Summary: “We show how to speed up two string-matching algo- rithms: the Boyer-Moore algorithm (BM algorithm), and its version called here the reverse factor algorithm (RF algorithm).  ...  The RF algorithm is based on factor graphs for the reverse of the pattern.  ... 

Towards a high-level implementation of flexible parallelism primitives for symbolic languages

Amadeo Casas, Manuel Carro, Manuel Hermenegildo
2007 Proceedings of the 2007 international workshop on Parallel symbolic computation - PASCO '07  
Summarizing, AI-AKL is part of an analyzer for the AKL language; Ann is the parallelized versión of one of the &-Prolog parallelizers; Boyer is a reduced versión of the Boyer-Moore theorem prover; Deriv  ...  We expect this separation of concerns to make it possible to easily explore variations on execution schemes, such as goal scheduling, supporting sophisticated goal dependencies, etc., to better suit the  ... 
doi:10.1145/1278177.1278193 dblp:conf/issac/CasasCH07 fatcat:7gclfhjgqnc4vhd3b2falrvk2e

Shift-or string matching with super-alphabets

Kimmo Fredriksson
2003 Information Processing Letters  
The well-known shift-or algorithm solves this problem in time O(n m/w ), where w is the number of bits in machine word, using bit-parallelism.  ...  The algorithm is implemented, and we show that it works well in practice too. The result is the fastest known algorithm for exact string matching for short patterns and small alphabets.  ...  We have shown that using super-alphabet in sift-or algorithm results in large speed-up, while retaining the simplicity of the original method.  ... 
doi:10.1016/s0020-0190(03)00296-5 fatcat:pxih6rhiujci3cic4upkis7jvi

Fast nGram-Based String Search Over Data Encoded Using Algebraic Signatures

Witold Litwin, Riad Mokadem, Philippe Rigaux, Thomas J. E. Schwarz
2007 Very Large Data Bases Conference  
Our search method combines the sublinear traversal of the record (as in Boyer Moore or Knuth-Morris-Pratt) with the agglomeration of parts of the record and search pattern into a single character -the  ...  Boyer-Moore.  ...  Our algorithm uses n-gram signatures combined with a sublinear traversal of the record similar to the algorithm by Boyer and Moore.  ... 
dblp:conf/vldb/LitwinMRS07 fatcat:e3nak4gcc5a5big7hcqdavn35m

Alternative Algorithms for Bit-Parallel String Matching [chapter]

Hannu Peltola, Jorma Tarhio
2003 Lecture Notes in Computer Science  
We consider bit-parallel algorithms of Boyer-Moore type for exact string matching. We introduce a two-way modification of the BNDM algorithm.  ...  We report experiments where we compared the new algorithms with existing ones. The simplified BNDM is the most promising of the new algorithms in practice.  ...  At the monent we are working on a combination method of SBNDM and TNDM. SBNDM showed to be the best of the new algorithms. As it often happens, algorithms with tight loops are also efficient.  ... 
doi:10.1007/978-3-540-39984-1_7 fatcat:ry5gm2ncrrb6bahav7pfjjnigy

Experimental results on string matching algorithms

Thierry Lecroq
1995 Software, Practice & Experience  
We compare these algorithms through two aspects: the number of text character inspections and the running time.  ...  These experiments show that for large alphabets and small patterns the Quick Search algorithm of Sunday is the most efficient and that for small alphabets and large patterns it is the Reverse Factor algorithm  ...  Boyer-Moore The Boyer-Moore algorithm 9 scans the characters of the window from right to left beginning with the rightmost character of the window.  ... 
doi:10.1002/spe.4380250703 fatcat:kwdnosztjze47et3peebgg7x5i

Page 1034 of Mathematical Reviews Vol. , Issue 92b [page]

1992 Mathematical Reviews  
. 212-223); Richard Cole, Tight bounds on the complexity of the Boyer-Moore string matching algorithm (pp. 224-233); Bala Kalyanasundaram and Kirk Pruhs, On-line weighted matching (pp. 234-240); Neal Young  ...  Frederickson, Optimal algorithms for tree partitioning (pp. 168-177); Pierre Kelsen and Vijaya Ramachan- dran, On finding minimal 2-connected subgraphs (pp. 178-187); Farid Alizadeh, A sublinear-time randomized  ... 
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