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iterated sum

3 messages · 水静流深, (Ted Harding), arun

#
On 14-Dec-2013 10:46:10 ???????? wrote:
x <- c(1,4,9,20,3,7)
  N <- length(x)

  x[1:(N-1)] + x[2:N]
  # [1]  5 13 29 23 10

Best wishes,
Ted.

-------------------------------------------------
E-Mail: (Ted Harding) <Ted.Harding at wlandres.net>
Date: 14-Dec-2013  Time: 10:54:00
This message was sent by XFMail
#
Hi,
Try:

?x[-1]+x[-length(x)]

A.K.
On Saturday, December 14, 2013 5:46 AM, ???? <1248283536 at qq.com> wrote:
x<-c(1,4,9,20,3,7)
i want to get a serie c(5,13,29,23,10).
y <- c()
for (i in 2:length(x)){
? ?  y[i-1] <- x[i-1]+x[i]}

is there more simple way to get?
??? [[alternative HTML version deleted]]

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