String functions in R

August 25, 2011
By

(This article was first published on Digithead's Lab Notebook, and kindly contributed to R-bloggers)

Here's a quick cheat-sheet on string manipulation functions in R, mostly cribbed from Quick-R's list of String Functions with a few additional links.

  • substr(x, start=n1, stop=n2)
  • grep(pattern,x, value=FALSE, ignore.case=FALSE, fixed=FALSE)
  • gsub(pattern, replacement, x, ignore.case=FALSE, fixed=FALSE)
  • gregexpr(pattern, text, ignore.case=FALSE, perl=FALSE, fixed=FALSE)
  • strsplit(x, split)
  • paste(..., sep="", collapse=NULL)
  • sprintf(fmt, ...)
  • toupper/tolower(x)
  • nchar(x)

Also see Regular Expressions as used in R and R String processing.

Note: Just to be clear, R is far from an ideal platform for processing text. For anything where that's the major concern, you're better off going to Python or Ruby.

To leave a comment for the author, please follow the link and comment on his blog: Digithead's Lab Notebook.

R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web Scraping) statistics (regression, PCA, time series, trading) and more...



If you got this far, why not subscribe for updates from the site? Choose your flavor: e-mail, twitter, RSS, or facebook...

Comments are closed.