Displaying 1 result from an estimated 1 matches for "permutatematrix".
2011 Mar 08
1
Replacing values in a data.frame/matrix
...like to define a permutation, e.g. 1 -> 2, 2 -> 1, 3 -> 3 and apply
it to the matrix. Thus, the following matrix should result:
m.perm <- matrix(c(2,1,3,1,2,3,3,2,1), ncol = 3, byrow=T)
i.e. each 1 should map to 2 and vice verse while 3 maps to itself. What
I've done so far is:
permutateMatrix <- function(mat, perm=NULL) {
values <- 1:NCOL(mat)
if (is.null(perm)) {
perm <- sample(values)
}
newmat <- replace(mat, sapply(values, function (val) which(mat==val)),
rep(perm, each=NROW(mat)))
return(list(mat.perm=newmat, perm=perm))
}
"perm" is the p...