[R] for loop vectorization

[miraceti]

Hi, I am still not familiar with vectorization.
Could you help with making this for loop more efficient?
The code is trying to make a Q matrix for a multidimensional state space
with specific conditions.

thanks
Mira


tmp = 0:(maxvals[1])
for(i in 2:nchars) {
  tmp <- outer(tmp, 0:(maxvals[i]), FUN="paste", sep=".")
}
states = tmp
stateidx = array(1:length(states), dim=dim(states))
transition <- matrix(data=0, nrow=length(states), ncol=length(states))

findstatedim <- function(x) which(stateidx==x, arr.ind = TRUE)
manhattandistance <- function(x,y) sum(abs(findstatedim(x)-findstatedim(y)))

    for(i in 1:length(states)) {
      for (j in 1:length(states)) {
        if (manhattandistance(i, j)==1) {
          if (sum(findstatedim(i)-findstatedim(j)) < 0) {
            transition[i,j] = "gain"
            if (findstatedim(i)[findstatedim(i)-findstatedim(j) == -1] == 1)
{
              transition[i,j] = "firstgain"
            }
          }
          else {
            transition[i,j] = "loss"
          }
        }
      }
    }
transition

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