[R] random walk on graph
Eric Blabac
emblabac at hotmail.com
Thu Apr 27 17:27:39 CEST 2006
Hi all,
I'm having issues coding a random walk on a fully connected, undirected
graph G with probability transition matrix P = (p_ij). Here is what I have
so far ...
for(i in 1:n){
for(m in 1:M){
x <- as.vector(matrix(rep(0,N+1),nc=N+1))
x[1] <- i
for(k in 2:N+1){
y <- as.vector(matrix(rep(0,n),nc=n))
r <- runif(1)
c <- c(0,cumsum(P[x[k-1],]))
for(j in 1:n){
y[j] <- (r >= c[j] & r < c[j+1])
}
x[k] <- which(y == 1)
}
L[i,m] <- x[N+1]
}
}
its giving me the error:
Error in "[<-"(`*tmp*`, k, value = integer(0)) :
nothing to replace with
no matter what I do I cant fix it ... any suggestions ?
Thanks
Eric Blabac
PhD Student - ASU Dept of Mathematics/Statistics
More information about the R-help
mailing list