[R] selecting ith rows of a matrix

[baptiste auguie]

Try this,


>  a = matrix(rnorm(10*10),ncol=10)
>  a[, seq(1,ncol(a),by=2)]

baptiste

On 29 Apr 2009, at 09:28, Umesh Srinivasan wrote:

> Hi all,
>
> If  I have a huge matrix/ dataframe and I want to create a new matrix/
> dataframe with every second (or third, or fourth etc.) row of the  
> original
> matrix, how can I do it? Any help much appreciated.
>
> Thanks,
> Umesh
>
> 	[[alternative HTML version deleted]]
>
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_____________________________

Baptiste Auguié

School of Physics
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