Eilenberg–Steenrod axioms: Difference between revisions
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In [[computer science]], a '''substring index''' is a [[data structure]] which gives [[substring]] search in a text or text collection in [[sublinear]] time. If you have a document <math>S</math> of length <math>n</math>, or a set of documents <math>D=\{S^1,S^2, \dots, S^d\}</math> of total length <math>n</math>, you can locate all occurrences of a pattern <math>P</math> in <math>o(n)</math> time. (See [[Big O notation]].) | |||
The phrase '''full-text index''' is also often used for an index of all substrings of a text. But is ambiguous, as it is also used for regular word indexes such as [[inverted file]]s and [[document retrieval]]. See [[full text search]]. | |||
Substring indexes include: | |||
* [[Suffix tree]] | |||
* [[Suffix array]] | |||
* N-gram index, an [[inverted file]] for all [[N-gram]]s of the text | |||
* [[Compressed suffix array]]<ref>R. Grossi and J. S. Vitter, [http://www.di.unipi.it/~grossi/PAPERS/sicomp05.pdf Compressed Suffix Arrays and Suffix Trees, with Applications to Text Indexing and String Matching], ''SIAM Journal on Computing,'' 35(2), 2005, 378-407.</ref> | |||
* [[FM-index]] | |||
* [[LZ-index]] | |||
== References == | |||
{{reflist}} | |||
[[Category:Algorithms on strings]] | |||
[[Category:String data structures]] | |||
[[Category:Database index techniques]] | |||
[[Category:Substring indices| ]] | |||
Latest revision as of 15:18, 3 August 2013
In computer science, a substring index is a data structure which gives substring search in a text or text collection in sublinear time. If you have a document of length , or a set of documents of total length , you can locate all occurrences of a pattern in time. (See Big O notation.)
The phrase full-text index is also often used for an index of all substrings of a text. But is ambiguous, as it is also used for regular word indexes such as inverted files and document retrieval. See full text search.
Substring indexes include:
- Suffix tree
- Suffix array
- N-gram index, an inverted file for all N-grams of the text
- Compressed suffix array[1]
- FM-index
- LZ-index
References
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- ↑ R. Grossi and J. S. Vitter, Compressed Suffix Arrays and Suffix Trees, with Applications to Text Indexing and String Matching, SIAM Journal on Computing, 35(2), 2005, 378-407.