How can I adress the current index of a vector? I want to work with time series and therefore give the n-th element of a vector some value dependent on the value of the n-1th element. Thank you in advance.
Mag. Ferri Leberl wrote:> How can I adress the current index of a vector?How do you define "current" in this context? You might want to get the length() of the vector... Uwe Ligges> I want to work with time series and therefore give the n-th element of a > vector some value dependent on the value of the n-1th element. > > Thank you in advance. > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Mag. Ferri Leberl wrote:> How can I adress the current index of a vector? > > I want to work with time series and therefore give the n-th element of a > vector some value dependent on the value of the n-1th element.Sorry, your question is not really clear, but possibly the following may help: 1) If you have a vector x, you can create a shifted vector by removing the first element, e.g.: xnew <- x[-1] + somevalue # or apply a function f(x[-1]) 2) The last element can be removed with: xnew <- x[-length(x)] 3) ... and sometimes vector concatenation ?c or the ?ifelse function can be useful in such circumstances. Thomas P. PS: there is more about such things in the docs.