Johannes Graumann wrote: > Hi all, > > I'm to inexperienced to come up with the matrix solution elusively > appearing on the horizon for the following problem and would appreciate if > you could give me a nudge ... > I have two vectors a, and b and need to find the closest match for each > value of a in b. > How to do that efficiently?
I am not sure if I understood your problem correctly, but maybe this is of help. However its not memory efficient. > a <- c(3,10,50,100) > b <- c(7,8,300) > b[apply(abs(outer(a,b,"-")),1,which.min)] [1] 7 8 8 8 In Biobase there is the matchpt function doing this efficiently. best wishes, ido ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
