try this, if your data frame name is "tab" mean.tab = data.frame (meanA = mean(tab[tab$name == 'a' ,4:8]), meanB = mean(tab[tab$name == 'b',4:8]), meanC = mean(tab[tab$name == 'c',4:8])) mean.tab good luck Romain
Romain Lorrillière UMR 8079 Laboratoire Ecologie, Systématique et Evolution Bât. 362 Université Paris-Sud 91405 Orsay cedex France tel : 01 69 15 56 85 fax : 01 69 15 56 96 mobile : 06 81 70 90 70 email : [EMAIL PROTECTED] [EMAIL PROTECTED] a écrit : Dear all, I have a dataset Exp name id x1 x2 x3 x4 x5 1 a 1 23 24 23 22 30 1 b 2 25 26 27 23 24 1 c 3 32 19 23 25 28 2 a 4 28 32 24 26 27 2 b 5 23 24 25 26 28 2 c 6 23 31 30 38 23 3 a 7 24 25 31 27 29 3 b 8 28 25 26 32 28 3 c 9 21 31 28 23 29 where each name a,b and c is repeated three times. Now I want to calculate the the averages of a,b and c over the three experiments for each x. For example for x1 I want to calculate the average of a like [a(from exp1) + a(exp2)+ a(exp3)]/3= (23+28+24)/3 How can I do that ? Thanks for your help, Regards, Antonia ______________________________________________ [EMAIL PROTECTED] mailing list [3]https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide [4]http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. References 1. mailto:[EMAIL PROTECTED] 2. mailto:[email protected] 3. https://stat.ethz.ch/mailman/listinfo/r-help 4. http://www.R-project.org/posting-guide.html ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
