[R] simulate binary markov chain

Hi all, I was hoping somebody may know of a function for simulating a large binary sequence (length >10 million) using a (1st order) markov model with known (2x2) transition matrix. It needs to be reasonably fast. I have tried the following; mc<-function(sq,P){ s<-c() x<-row.names(P) n<-len

[R] sliding window over a large vector

Hi all, I have a very large binary vector, I wish to calculate the number of 1's over sliding windows. this is my very slow function slide<-function(seq,window){ n<-length(seq)-window tot<-c() tot[1]<-sum(seq[1:window]) for (i in 2:n) { tot[i]<- tot[i-1]-seq[i-1]+seq[i] }

Re: [R] sample consecutive integers efficiently

Charles C. Berry wrote: On Thu, 28 Aug 2008, Chris Oldmeadow wrote: Hi all, I have some rough code to sample consecutive integers with length according to a vector of lengths #sample space (representing positions) pos<-c(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20) #sam

[R] sample consecutive integers efficiently

Hi all, I have some rough code to sample consecutive integers with length according to a vector of lengths #sample space (representing positions) pos<-c(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20) #sample lengths lengths<-c(2,3,2) From these two vectors I need a vector of sampled pos

[R] sequence with start and stop positions

Hi, I have a vector of start positions, and another vector of stop positions, eg start<-c(1,20,50) stop<-c(7,25,53) Is there a quick way to create a sequence from these vectors? new<-c(1,2,3,4,5,6,7,20,21,22,23,24,25,50,51,52,53) the way Im doing it at the moment is pos<-seq(start[1],sto