Stata Tip 98: Counting Substrings within Strings
نویسندگان
چکیده
منابع مشابه
Reconstructing Strings from Substrings
We consider an interactive approach to DNA sequencing by hybridization, where we are permitted to ask questions of the form "is s a substring of the unknown sequence S?", where s is a specific query string. We are not told where s occurs in S, nor how many times it occurs, just whether or not s a substring of S. Our goal is to determine the exact contents of S using as few queries as possible. ...
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This article presents effective (dynamic) algorithm for solving a problem of counting the number of substrings of given string which are also substrings of second string. Presented algorithm can be used for example for quick calculation of strings similarity measure using generalized ngram method (Niewiadomski measure [2]), which are shown. Correctness and complexity analyses are included. 1 Oz...
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Given a length m string f over a k-ary alphabet and a positive integer n, we develop eecient algorithms to generate (a) all k-ary strings of length n that have no substring equal to f, (b) all k-ary circular strings of length n that have no substring equal to f, and (c) all k-ary necklaces of length n that have no substring equal to f, where f is an aperiodic necklace. Each of the algorithms ru...
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We establish a variety of combinatorial bounds on the tradeoos inherent in reconstructing strings using few rounds of a given number of substring queries per round. These results lead us to propose a new approach to sequencing by hybridization (SBH), which uses interaction to dramatically reduce the number of oligonucleotides used for de novo sequencing of large DNA fragments, while preserving ...
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This paper investigates the number of quantum queries made to solve the problem of reconstructing an unknown string from its substrings in a certain query model. More concretely, the goal of the problem is to identify an unknown string S by making queries of the following form: “Is s a substring of S?”, where s is a query string over the given alphabet. The number of queries required to identif...
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ژورنال
عنوان ژورنال: The Stata Journal: Promoting communications on statistics and Stata
سال: 2011
ISSN: 1536-867X,1536-8734
DOI: 10.1177/1536867x1101100212