Running sum

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

-roger
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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Running sum

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