[R] subsampling

[Romain François]

nicolas.deig at epfl.ch a écrit :

>hi,
>
>I would like to subsample the array c(1:200) at random into ten subsamples 
>v1,v2,...,v10.
>
>I tried with to go progressively like this:
>
>
>  
>
>>x<-c(1:200)
>>v1<-sample(x,20)
>>y<-x[-v1]
>>v2<-sample(y,20)
>>    
>>
>
>and then I want to do:
>
>  
>
>>x<-y[-v2]
>>    
>>
>Error: subscript out of bounds.
>
>__
>
You should try :

x[-c(v2,v1)]

But more accurately, try permutting the all x and choose the 20 firsts 
entries, the 20 after, ...
I think that will do the job

x  <- 1:200 
y  <- x[sample(200)]
v1 <- y[ 1:20]
v2 <- y[21:40]
...

Regards.

Romain.

-- 
Romain FRANCOIS : francoisromain at free.fr
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