extracting a sub data frame by value of one of its columns
On Sun, 7 May 2000, Faheem Mitha wrote:
Dear R people, This should be a straightforward operation, but I am having difficulties. I have a data frame with three columns, call them a, b, and c. c is a column of factors, 1...10. I want to extract all the rows for which c has the value say 1, and put them in a separate data frame. I looked at the various sort functions provided, but see no way to easily adapt them to my needs.
Nothing to do with sorting as far as I can see. Try df2 <- df1[df1$c == 1,] and note that indexing is pretty central to using S (the language), so it is worth learning all the ways to use it.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272860 (secr) Oxford OX1 3TG, UK Fax: +44 1865 272595 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._