[R] sampling without repetition

[Thomas W Blackwell]

Rajarshi  -

To obtain three disjoint subsets, I would do

indic <- sample(seq(3), length(r), TRUE)
s1 <- r[indic == 1]
s2 <- r[indic == 2]
s3 <- r[indic == 3]

Note that the sizes of the three subsets have a
joint multinomial distribution with parameters
prob = c(1/3, 1/3, 1/3)  and  n = length(r).

-  tom blackwell  -  u michigan medical school  -  ann arbor  -

On Mon, 17 Nov 2003, Rajarshi Guha wrote:

> On Mon, 2003-11-17 at 20:01, Thomas W Blackwell wrote:
> > Rajarshi  -
> >
> > Do you want three sets, three disjoint sets, or sets of
> > size three ?  It's not clear what you are attempting to do.
>
> Sorry about that. I wanted to select 3 disjoint sets from a supplied
> vector of numbers. My initial example had
>
> r <- 1:300
>
> but there is no guarantee that r will contain a consecutive sequence of
> numbers.
>
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> Rajarshi Guha <rxg218 at psu.edu> <http://jijo.cjb.net>
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