[R] FW: Select a random subset of rows out of matrix

[Paul Hiemstra]

Hi,

You could try something like this:

nrow = 1000
ncol = 10
nosample = 50
m = matrix(runif(10000), nrow = nrow, ncol = ncol)
# Randomly select 50 row numbers and extract the data
m_subset = m[sample(1:nrow, size = nosample),]

cheers,
Paul

Haenlein.Michael wrote:
> Dear all,
>
> I have a large dataset (N=100,000 with 89 variables per subject). This dataset is stored in a 100.000 x 89 matrix where each row describes one individual and each column one variable.
>
> What is the easiest way of selecting a subset of let's say 1.000 individuals out of that whole matrix?
>
> Thanks,
>
> Michael
>
>
> Michael Haenlein
> Associate Professor of Marketing
> ESCP-EAP European School of Management
> Paris, France
>
> 	[[alternative HTML version deleted]]
>
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-- 
Drs. Paul Hiemstra
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