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Published byNickolas Chapman Modified over 9 years ago
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Regular Expressions Pattern and String Matching in Text
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What is a RegEx “Find” option but fancier Match a “pattern” to a “string” Cheat sheet: http://www.rexegg.com/regex-quickstart.htmlhttp://www.rexegg.com/regex-quickstart.html Different coding languages have different RegEx syntax But you can usually set them to read any of the other syntaxes My favorite RegEx tester is: http://www.regexr.com/http://www.regexr.com/
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Find any word that starts with a capital letter:
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Find any word that starts with a capital letter and then a lower case letter:
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Match a phrase that might be arranged differently:
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Or dates… You can get about as fancy with this as you’d like Useful to parse larger chunks of text entered by date or number
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Example Uses: Syria Militant Networks and Violence in Syria What sorts of networks are likely to result in infighting as opposed to alliances?
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Example Uses:.gov Searching terabytes of this…..
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To get counts: To say something about government attention to different issues 2008 Agency Relative Emphasis
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RegEx: what it isn’t good for Time consuming to do pattern matching over large data When you have a lot of variation in spelling or phrasing Fuzzy Sets! Useful reference for fuzzy matches: http://www.r- bloggers.com/fuzzy-string-matching-a-survival-skill-to-tackle- unstructured-information/http://www.r- bloggers.com/fuzzy-string-matching-a-survival-skill-to-tackle- unstructured-information/
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