Select a random subset of rows out of matrix
On Mar 16, 2009, at 10:34 AM, 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?
bigmatrix[ sample( 1:nrow(bigmatrix), 1000, replace=FALSE), ]
Thanks, Michael Michael Haenlein Associate Professor of Marketing ESCP-EAP European School of Management Paris, France [[alternative HTML version deleted]]
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