On Tue, 2005-08-16 at 13:18 -0400, Allan Strand wrote: > Hi All, > > I'm trying to take a numerical vector and produce a new vector of the > same length where each element in the first is placed into a category > given by a 'breaks-like' vector. The values in the result should equal > the lower bounds of each category as defined in the breaks vector. > > I suspect that a vectorized solution is pretty simple, but I can't > seem to figure it out today. Here is an example of my problem: > > Vector 'a' is the original vector. Vector 'b' gives the lower bounds > of the categories. Vector 'c' is the result I am seeking. > > a <- c(0.9, 11, 1.2, 2.4, 4.0, 5.0, 7.3, 8.1, 3.3, 4.5) > b <- c(0, 2, 4, 6, 8) > > c <- c(0, 8, 0, 2, 4, 4, 6, 8, 2, 4) > > Any suggestions would be greatly appreciated. > > cheers, > Allan Strand
See ?cut > a <- c(0.9, 11, 1.2, 2.4, 4.0, 5.0, 7.3, 8.1, 3.3, 4.5) > b <- c(0, 2, 4, 6, 8) > cut(a, c(b, Inf), labels = b, right = FALSE) [1] 0 8 0 2 4 4 6 8 2 4 Levels: 0 2 4 6 8 Note that cut() returns a factor. HTH, Marc Schwartz ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html