[R] Running sum

[Roger D. Peng]

You could try using embed(), but I doubt it's faster.

-roger

Sean Davis wrote:
> I have vector X of length N that I want to have a running sum for 
> (called Y).  I just need max(Y).  I do this with a "for" loop like so:
> 
>     Y <- vector(length=N)
>     Y[1] <- X[1]
>     for (i in 2:N) {
>       Y[i] <- Y[i-1]+X[i]
>     }
>     return(max(Y))
> 
> Is there a faster way to do this?
> 
> Thanks,
> Sean
> 
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-- 
Roger D. Peng
http://www.biostat.jhsph.edu/~rpeng/