[R] tapply and grouping

Hello all, I have a df like this: w - c(1.20, 1.34, 2.34, 3.12, 2.89, 4.67, 2.43, 2.89, 1.99, 3.45, 2.01, 2.23, 1.45, 1.59) g - rep(c(a, b), each=7) df - data.frame(g, w) df # 1. Mean for each group tapply(df$w, df$g, function(x) mean(x)) # 2. Range for each group - fix value 0.15

Re: [R] tapply and grouping

Is this what you want: w - c(1.20, 1.34, 2.34, 3.12, 2.89, 4.67, 2.43, + 2.89, 1.99, 3.45, 2.01, 2.23, 1.45, 1.59) g - rep(c(a, b), each=7) df - data.frame(g, w) df gw 1 a 1.20 2 a 1.34 3 a 2.34 4 a 3.12 5 a 2.89 6 a 4.67 7 a 2.43 8 b 2.89 9 b 1.99 10 b 3.45 11 b 2.01 12