String Matching Algorithms

It is a basic introduction to "String Matching Algorithms". Useful for Biotechnology, Bioinformatics, Computer Science.

For ".pptx" version read "Contact Me" slide in the end of the presentation.

Transcript

1. STRING MATCHING ALGORITHMS Google images
2. OUTLINE  What is String?  What is String Matching?  Definition of Algorithm  String Matching Algorithms  String Matching Algorithms Applications
3. WHAT IS STRING?  In computer programming, a string is traditionally a sequence of characters, either as constant or as some kind of variable  E.g. ABCABDC or 1Ac35D Google images
4. WHAT IS STRING?  String may be applied in Bioinformatics to describe DNA strand composed of nitrogenous bases Google images
5. WHAT IS STRING MATCHING?  String matching is finding occurrence(s) of a pattern string within another string or body of text  E.g. We have a string “BCATDOG” and the pattern to be searched is “CAT”. Now finding “CAT” in the string “BCATDOG” is string matching
6. WHAT IS STRING MATCHING?  Uses for the string matching include:  Finding a text in a document file or in a report  Used by different search engines like: Google Google images
7. EXAMPLE Google images
8. DEFINITION OF ALGORITHM  Algorithm is formula or set of rules followed for solving a problem.  Example: Searching algorithms, sorting algorithms, etc. Google images
9.  Example: Algorithm for checking a lamp Google images
10. STRING MATCHING ALGORITHMS  Brute Force Algorithm  Karp-Rabin Algorithm  Boyer-Moore Algorithm
11. BRUTE FORCE ALGORITHM  Simplest string matching algorithm  Steps:  Match the first character of the pattern with the first character of the string  If succeed, try to match the second character, and then third and so on
12. BRUTE FORCE ALGORITHM  If hit a failure point, slide the pattern over one character and try again  When a match is found, return its starting location  Example:  Given string “BCCATDOG”  Pattern to match is “CAT”
13. EXAMPLE
14. ALGORITHM FOR EXAMPLE Step1: Match the first character of the pattern with the first character of the string Step3: If hit a failure point, slide the pattern over one character and try again Step2: If succeed, try to match the next character, and so on Step4: When a match is found, return its starting location Starting location for the pattern in the string is “3”
15. STRING MATCHING ALGORITHMS APPLICATIONS Besides Computer Science, String matching algorithms have some other applications:  Detecting Plagiarism: it is the process of locating instances of plagiarism within a work or document  Bioinformatics String algorithms are centrally important in bioinformatics for dealing with sequence information
16. CONT.  Molecular biology Approximate matching of a search pattern to a target text is a fundamental tool in molecular biology  Computer Science Exact string matching is more useful in computer science
17. CONT.  Text Mining Research: includes information extraction, topic tracking, content summarization, information visualization, question answering, concept linkage, text classification, and text clustering
18. Google images
19. Google images
20. CONTACT ME  If you want the resources and further understanding on this topic contact me via my email:  cmptrsntst@yahoo.com  Copy, cut do anything you want!!