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R Web Scraping Quick Start Guide

You're reading from   R Web Scraping Quick Start Guide Techniques and tools to crawl and scrape data from websites

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Product type Paperback
Published in Oct 2018
Publisher Packt
ISBN-13 9781789138733
Length 114 pages
Edition 1st Edition
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Olgun Aydin Olgun Aydin
Author Profile Icon Olgun Aydin
Olgun Aydin
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XML Path Language and Regular Expression Language

XPath primarily handles the nodes of XML 1.0 or XML 1.1 trees. It is used to represent the hierarchical structure of an XML document. XPath uses non-XML syntax and works on the logical structure of XML documents. This structure is also known as the data model. XPath is designed to be used embedded into a programming language. It has a natural subset that can be used for mapping.

A regular expression, regex or regexp, represents a search model used in computer science. Regex emerged as a result of the work of the American mathematician Stephen Cole Kleene in the 1950s. It is also being used with Unix text-processing programs. There are different forms of syntax for writing regular expressions: the POSIX standard and Perl syntax. A regular expression in search engines is used in search and replace operations and lexical analysis...

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