[R] How to extract every nth element from a vector

[Martyn Plummer]

On 28-Mar-01 Barry Cooke wrote:
> R-helpers:
> 
> Is there a simple way to extract every nth element from a very long vector?

window() will do this.  For example,
R> x <- 1:100
R> window(x, deltat=10)
 [1]  1 11 21 31 41 51 61 71 81 91
attr(,"tsp")
[1]  1.0 91.0  0.1

This will set the "tsp" attribute, which may be a nuisance, but you can
take this off.

Martyn
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