Is there any R function for data normalization?
On 12-10-02 5:51 AM, Rui Esteves wrote:
Hello, I have a matrix with values, with columns c1..cn. I need the values to be normalized between 0 and 1 by column. Therefor, the 0 should correspond to the minimum value in the column c1 and 1 should correspond to the maximum value in the column c1. The remaining columns should be organized in the same way. Does a function in R exists for this purpose?
No, but it is easy to construct one using sweep. First subtract column
mins, then divide by column maxes:
normalize <- function(x) {
x <- sweep(x, 2, apply(x, 2, min))
sweep(x, 2, apply(x, 2, max), "/")
}
Duncan Murdoch