Dear all,

I'm trying to optimize code and want to avoid for-loops as much as possible.
I'm applying a calculation on subvectors from a big one, and I get the
subvectors by using a vector of starting positions:

x <- 1:10
pos <- c(1,4,7)
n <- length(x)

I try to do something like this :
pos2 <- c(pos, n+1)

out <- c()
for(i in 1:n){
     tmp <- x[pos2[i]:pos2[i+1]]
     out <- c(out, length(tmp))
}

Never mind the length function, I apply a far more complicated one. It's
about the use of the indices in the for-loop. I didn't see any way of doing
that with an apply, unless there is a very convenient way of splitting my
vector in a list of the subvectors or so.

Anybody an idea?
Cheers
-- 
Joris Meys
Statistical Consultant

Ghent University
Faculty of Bioscience Engineering
Department of Applied mathematics, biometrics and process control

Coupure Links 653
B-9000 Gent

tel : +32 9 264 59 87
Joris.Meys@Ugent.be
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