PPT-Regular expressions and the Corpus Query Language

Albert Gatt Corpus search These notes introduce some practical tools to find patterns regular expressions the corpus query language CQL developed by the Corpora and Lexicons Group University of Stuttgart. and Answer . Inference . for . Telegraphic Entity-seeking . Queries. EMNLP 2014. Mandar Joshi. Uma Sawant. Soumen Chakrabarti. IBM Research. IIT Bombay, Yahoo Labs. IIT Bombay. mandarj90@in.ibm.com. uma@cse.iitb.ac.in. Hira. . Waseem. Lexical Analysis . Input Buffering. Before discussing the problem of recognizing lexemes in the input, let us examine some ways that the simple but important task of reading the source program can be speeded. . CS 4705. Some . slides adapted . from Hirschberg, Dorr/. Monz. , . Jurafsky. Some simple problems: . How much is Google worth?. How much is the Empire State Building worth?. How much is Columbia University worth?. Definitions. Equivalence to Finite Automata. 2. RE. ’. s: Introduction. Regular expressions. describe languages by an algebra.. They describe exactly the regular languages.. If E is a regular expression, then L(E) is the language it defines.. analysis. David Kauchak. CS159 – Spring 2011. Administrivia. Assignment 0 due today. article discussion. Assignment 1 out soon. due Wednesday, 2/2 in class. no code submitted, but will require coding. Formal definition of a regular expression.. Languages associated with regular expressions.. Introduction regular grammars. . Regular language and homomorphism. . The Chomsky Hierarchy . Regular Expression. Reading: Chapter 3. 2. Regular Expressions vs. Finite Automata. Offers a declarative way to express the pattern of any string we want to accept . E.g., . 01*+ 10*. Automata => more machine-like . < input: string , output: [accept/reject] >. 2015.03.16. Front End. The purpose of the front end is to deal with the input language. Perform a membership test: code . . source language?. Is the program well-formed (semantically) ?. Build an . http://xkcd.com. /. 208. Cleverbot. video. http://www.youtube.com/watch?v=WnzlbyTZsQY. CORpus. analysis. David Kauchak. NLP – . Fall . 2014. Administrivia. Assignment 0. Assignment . 1 out. due . Regular Expressions Pattern Matching in Strings February 13, 2019 Regular Expressions 1 More about strings In a previous lecture, we discussed the String class and its methods Powerful class with many Chapter 3 REGULAR LANGUAGES AND REGULAR GRAMMARS Learning Objectives At the conclusion of the chapter, the student will be able to: Identify the language associated with a regular expression Find a regular expression to describe a given language aho@cs.columbia.edu. JerseySTEM. Math Club. March 5, 2017. Introduction. Regular expressions are a powerful notation for specifying patterns in text strings.. Regular expressions are used routinely in such applications as text editors, language translators, and Internet packet processors.. CS159 – Spring 2011. Administrivia. Assignment 0 due today. article discussion. Assignment 1 out soon. due Wednesday, 2/2 in class. no code submitted, but will require coding. Send me an e-mail if you’d like me to e-mail announcements to another account besides your school account. 2. Regular Expressions vs. Finite Automata. Offers a declarative way to express the pattern of any string we want to accept . E.g., . 01*+ 10*. Automata => more machine-like . < input: string , output: [accept/reject] >.