[R] Select fixed number of elements

[Ken Knoblauch]

Alaios <alaios <at> yahoo.com> writes:

> I have in my code some vectors that are not of equal size. 
I would like to be able for each of these vectors
> select 6 elements that are (almost) equally spaced. 
So the first one would be at (or close) to the beginning
> the last one at (or close) to the end and the other 4 
equally spaced between first and last element.
> 
> How can I do something like that on a vector of
 not known size?
> 
> I would like to thank you in advance 
for your help
Would something like this be what you are
looking for?

N <- 20
set.seed(16121952)
x <- runif(N)
x
rx <- range(x)
br <- seq(rx[1], rx[2], len = 6)
sapply(br, function(bx){
	x[which.min(abs(x - bx))]
})

[1] 0.02910779 0.22708582 0.39239718 
     0.52419265 0.68940262 0.86889817

> 
> Regards
> Alex

-- 
Kenneth Knoblauch
Inserm U846
Stem-cell and Brain Research Institute
Department of Integrative Neurosciences
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