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    DATA MINING
     Desktop Survival Guide by Graham Williams  | 
    
    
     
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R provides the usual string type and string manipulation functions:
> chartr("a-m", "m-z", "abcdef")	 # "mnopqr"
> grep
> nchar
> sub
> substr
> tolower("ABCdef")			 # "abcdef"
> toupper("ABCdef")			 # "ABCDEF"
> pmatch("png", c("jpeg", "png", "gif")) # 2
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R provides some useful predefined variables, including:
> letters # a b c d [...] z > LETTERS # A B C D [...] Z  |