R help - Aug 2001 - sample()

Dear R users,

is there a way to extract directly rows instead of column vectors 
using the function sample()?
I have already tried to transpose and back-transpose my dataframe, 
but I couldn't manage to get rid off the levels in the resulting 
dataframe.

Macintosh G4 (Mac OS9.1), R Version 1.3.0

Any help is welcome!

Christof

-- 
Christof Bigler
Mountain Forest Ecology
ETH-Zentrum HG G21.4
CH-8092 Zurich, Switzerland
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On Thu, 2 Aug 2001, Christof Bigler wrote:
> Dear R users,
>
> is there a way to extract directly rows instead of column vectors
> using the function sample()?
> I have already tried to transpose and back-transpose my dataframe,
> but I couldn't manage to get rid off the levels in the resulting
> dataframe.
>
Sample from 1:n (or from the row names) and use this as an index to the
dataframe

eg
data(trees)
index<-seq(length=NROW(trees))
trees[sample(index,10),]

or
library(MASS)
data(hills)
hills[sample(rownames(hills),10),]


	-thomas

Thomas Lumley			Asst. Professor, Biostatistics
tlumley at u.washington.edu	University of Washington, Seattle

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