Re: [R-sig-eco] Select a percentage of combinations

Hi Lara, You want to subset out 20% of the columns from a matrix, at random. Try: combinations <- combn(20,3) ## makes the 'all combinations' matrix sample <- combinations[,sample(1:ncol(combinations), floor(ncol(combinations)*0.2))] ## subsets out 20% of the columns from that object. ## Note

[R-sig-eco] Select a percentage of combinations

Hello, I want to select sets of combinations, but I do not want use all 1140 combn (20,3) choose (20,3) - total of 1140. [,1091] [,1092] [,1093] [,1094] [,1095] [,1096] [,1097] [,1098] [,1099] [,1100] [1,] 13 13 13 13 13 13 13 13 13 13 [2,]