Hi, Why is the result of below "apply" call rotated with respect to the input and how to remedy this? Thanks, Joh .ZScore <- function(input){ #cat(input,"\n") z <- (input - mean(input))/sd(input) return(z) } apply(data.frame(x1=c(1,2,3,4,5),x2=c(2,3,4,5,6),x3=c(3,4,5,6,7)),1,.ZScore)