Extracting Person Name, Date and Place from Text Document using LEX Tool

Abstract

Automata theory is closely related to formal language theory. Automata is used in designing and checking the behavior of digital circuits, lexical analysis, software for scanning large bodies of text and software verification, communications protocols. Finite automata have finite number of states. Finite automata provide efficient and convenient tools to represent the linguistic phenomena. If a text document is searched manually to get some important information, the process is slow, tedious and error prone. Manual searching commonly misses important information in the document and it causes wastage of time. It has been noted that finite state automata based techniques have been widely used in natural language processing and information extraction in various natural languages. In this thesis report various text extracting approaches are studied. Based on these approaches, a technique is given which extracts person name, place and date from text document using Lex tool. Regular expressions through which required information is extracted are also discussed.