Use 1:n as an index. e.g. sapply(1:n, function(i) cor(x[,i],y[,i]))
-- Bert On Thu, Feb 23, 2012 at 2:10 PM, Sam Steingold <s...@gnu.org> wrote: > suppose I have two sets of vectors: x1,x2,...,xN and y1,y2,...,yN. > I want N correlations: cor(x1,y1), cor(x2,y2), ..., cor(xN,yN). > my sets of vectors are arranged as data frames x & y (vector=column): > > x <- data.frame(a=rnorm(10),b=rnorm(10),c=rnorm(10)) > y <- data.frame(d=rnorm(10),e=rnorm(10),f=rnorm(10)) > > cor(x,y) returns a _matrix_ of all pairwise correlations: > > cor(x,y) > d e f > a 0.2763696 -0.3523757 -0.373518870 > b 0.5892742 -0.1969161 -0.007159589 > c 0.3094301 0.1111997 -0.094970748 > > which is _not_ what I want. > > I want diag(cor(x,y)) but without the N^2 calculations. > > thanks. > > -- > Sam Steingold (http://sds.podval.org/) on Ubuntu 11.10 (oneiric) X > 11.0.11004000 > http://www.childpsy.net/ http://iris.org.il http://americancensorship.org > http://dhimmi.com http://www.PetitionOnline.com/tap12009/ > http://jihadwatch.org > Never argue with an idiot: he has more experience with idiotic arguments. > > ______________________________________________ > 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. -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.
