Your apply is trying to take the correlations of the rows of mat1 with the columns of mat2 which, of course, does not work if they have different numbers of columns. I think you mean to take the correlations of the columns of mat1 with the columns of mat2. For example, to take the correlations of the 5 columns of mat1 with the first 4 columns of mat2 try:
> cor(mat1, mat2[,1:4]) col1 col2 col3 col4 col1 -0.34624254 -0.2669519 -0.2705077 0.2183249 col2 -0.26553255 -0.2687643 -0.0865895 0.1819025 col3 0.19474613 -0.2334986 0.1746522 0.2326915 col4 0.09328338 0.5117784 0.2413143 -0.3374916 col5 0.27519716 0.1605331 -0.4057137 0.3282105 On 7/24/07, Bernzweig, Bruce (Consultant) <[EMAIL PROTECTED]> wrote: > Hi, > > I've created the following two matrices (mat1 and mat2) and a function > (f) to calculate the correlations between the two on a row by row basis. > > mat1 <- matrix(sample(1:500,50), ncol = 5, > dimnames=list(paste("row", 1:10, sep=""), > paste("col", 1:5, sep=""))) > > mat2 <- matrix(sample(501:1000,50), ncol = 5, > dimnames=list(paste("row", 1:10, sep=""), > paste("col", 1:5, sep=""))) > > f <- function(x,y) cor(x,y) > > When the matrices are squares (# rows = # columns) I have no problems. > > However, when they are not (as in the example above with 5 columns and > 10 rows), I get the following error: > > > apply(mat1, 1, f, y=mat2) > Error in cor(x, y, na.method, method == "kendall") : > incompatible dimensions > > Any help would be appreciated. Thanks! > > - Bruce > > > > ********************************************************************** > Please be aware that, notwithstanding the fact that the pers...{{dropped}} > > ______________________________________________ > 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 > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ 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 and provide commented, minimal, self-contained, reproducible code.