R help - Aug 2012 - Sum of vector elements

Hi, Is it possible to avoid using do and while loops to calculate the sum of
the elements of a vector until the appearance of the first positive element.



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I'd do something like this:

x <- sample(seq(-10, 10))

sum(x[seq_len(which.max(x > 0)])

Though others might have more direct solutions.

which.max() gets you the index of the first time x > 0 -- seq_len
gives you numbers 1 to that index -- then just subset and sum like
normal.

Best,
Michael

On Tue, Aug 7, 2012 at 7:37 AM, number10 <havana_dream at ymail.com>
wrote:
> Hi, Is it possible to avoid using do and while loops to calculate the sum
of
> the elements of a vector until the appearance of the first positive
element.
>
>
>
> --
> View this message in context:
http://r.789695.n4.nabble.com/Sum-of-vector-elements-tp4639395.html
> Sent from the R help mailing list archive at Nabble.com.
>
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