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
[[alternative HTML version deleted]]
______________________________________________
[email protected] 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.
