Hi everybody, I have a small question about R. I'm doing some correlation matrices between my files. These files contains each 4 columns of data. These data files contains missing data too. It could happen sometimes that in one file, one of the 4 columns contains only missing data NA. As I'm doing correlations between the same columns of each files, I get a correlation matrix with a column containing only NAs such like this:
file1 file 2 file 3 file1 1 NA 0.8 file2 NA 1 NA file3 0.8 NA 1 For file2, I have no correlation coefficient. My function is looking for the highest correlation coefficient for each file. But I have an error message due to this. My question is: how can I say to the function: don't do any calculation if you see only NAs for the file you're working on? The aim of this function is to automatize this calculation for 300 files. I tried by adding: na.rm=TRUE, but it stills wants to do the calculation for the file containing only NAs (error: 0 (non-NA) cases). Could you tell me what I should add in my function? Thanks a lot! get.max.cor <- function(station, mat){ mat[row(mat) == col(mat)] <- -Inf which( mat[station, ] == max(mat[station, ], na.rm=TRUE) ) } -- View this message in context: http://r.789695.n4.nabble.com/Prevent-calculation-when-only-NA-tp4630716.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.