simple matrix question
Hoi Christoph, --On woensdag 4 juni 2003 15:21 +0200 Christoph Lehmann
<lehmann at puk.unibe.ch> wrote:
what is the easiest way to get from
x
x1 x2
[1,] 2 3
[2,] 3 2
[3,] 1 3
[4,] 1 4
xbar1
x1 x2
[1,] 1.75 3
[2,] 1.75 3
[3,] 1.75 3
[4,] 1.75 3
with the mean of the columns of x as values?
xbar1 <- tapply(as.vector(x), gl(2,4), mean);
Paul Lemmens NICI, University of Nijmegen ASCII Ribbon Campaign /"\ Montessorilaan 3 (B.01.03) Against HTML Mail \ / NL-6525 HR Nijmegen X The Netherlands / \ Phonenumber +31-24-3612648 Fax +31-24-3616066