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 |
R provides some useful predefined variables, including:
> letters # a b c d [...] z > LETTERS # A B C D [...] Z |