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
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_____________________________
Baptiste AuguiƩ
School of Physics
University of Exeter
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