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Táto stránka sa týka školského roku 2016/17. V školskom roku 2017/18 predmet vyučuje Jakub Kováč, stránku predmetu je https://people.ksp.sk/~kuko/ds


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==Theoretical results for edit distance computation==
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Exact algorithm O(mn) or improved by logarithimc factor.
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Approximation algorithm: For strings of length ''n'' and every fixed ε > 0 compute <math>(\log n)^{O(1/\epsilon)}</math> approximation in <math>n^{1+\epsilon}</math> time
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Source: Andoni A, Krauthgamer R, Onak K. Polylogarithmic approximation for edit distance and the asymmetric query complexity. FOCS2010, pp. 377-386 [http://web.mit.edu/andoni/www/papers/editQuery-focs.pdf]
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Conditional lower bound: If the edit distance can be computed in <math>O(n^{2-\delta})</math> for some constant δ > 0, then the satisfiability of conjunctive normal form (CNF) formulas with N variables and M clauses can be solved in time <math>M^{O(1)}2^{(1-\epsilon)N}</math> for a constant <math>\epsilon >
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0</math>, which would violate Strong Exponential Time Hypothesis (SETH).
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Source: Backurs A, Indyk P. Edit Distance Cannot Be Computed in Strongly Subquadratic Time (unless SETH is false). STOC2015, pp. 51-58 [http://arxiv.org/pdf/1412.0348v2.pdf]
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==Literatúra==
 
==Literatúra==
 
* Dan Gusfield (1997) [http://www.cambridge.org/uk/catalogue/catalogue.asp?isbn=0521585198 Algorithms on Strings, Trees and Sequences: Computer Science and Computational Biology.] Cambridge University Press. Prezenčne v knižnici so signatúrou I-INF-G-8.
 
* Dan Gusfield (1997) [http://www.cambridge.org/uk/catalogue/catalogue.asp?isbn=0521585198 Algorithms on Strings, Trees and Sequences: Computer Science and Computational Biology.] Cambridge University Press. Prezenčne v knižnici so signatúrou I-INF-G-8.
 
* Poznámky z predmetu Vyhľadávanie v texte [http://compbio.fmph.uniba.sk/vyuka/vvt/poznamky/main-2013-05-20.pdf] (zčasti písané študentami a nedokončené)
 
* Poznámky z predmetu Vyhľadávanie v texte [http://compbio.fmph.uniba.sk/vyuka/vvt/poznamky/main-2013-05-20.pdf] (zčasti písané študentami a nedokončené)

Verzia zo dňa a času 19:18, 4. apríl 2016

Theoretical results for edit distance computation

Exact algorithm O(mn) or improved by logarithimc factor.

Approximation algorithm: For strings of length n and every fixed ε > 0 compute (\log n)^{{O(1/\epsilon )}} approximation in n^{{1+\epsilon }} time

Source: Andoni A, Krauthgamer R, Onak K. Polylogarithmic approximation for edit distance and the asymmetric query complexity. FOCS2010, pp. 377-386 [1]

Conditional lower bound: If the edit distance can be computed in O(n^{{2-\delta }}) for some constant δ > 0, then the satisfiability of conjunctive normal form (CNF) formulas with N variables and M clauses can be solved in time M^{{O(1)}}2^{{(1-\epsilon )N}} for a constant \epsilon >0, which would violate Strong Exponential Time Hypothesis (SETH).

Source: Backurs A, Indyk P. Edit Distance Cannot Be Computed in Strongly Subquadratic Time (unless SETH is false). STOC2015, pp. 51-58 [2]


Literatúra